Watershed based plan for the Lake Thunderbird watershed

WATERSHED BASED PLAN
FOR THE
LAKE THUNDERBIRD WATERSHED
Photo courtesy of OTRD
Prepared By:
Oklahoma Conservation Commission
Water Quality Division
2800 N. Lincoln Blvd., Suite 160
Oklahoma City, OK 73105
(405) 522­4500
Lake Thunderbird WBP June 2010
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­Table
of Contents
LIST OF TABLES 3
LIST OF FIGURES 3
PREFACE 4
INTRODUCTION 6
CAUSES and SOURCES 7
LOAD REDUCTIONS 17
NPS MANAGEMENT MEASURES 18
PUBLIC OUTREACH 24
CRITERIA 26
IMPLEMENTATION SCHEDULE and INTERIM MILESTONES 28
MONITORING PLAN 31
TECHNICAL and FINANCIAL ASSISTANCE NEEDED 37
REFERENCES 38
Lake Thunderbird WBP June 2010
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­LIST
OF TABLES
Table 1. Population growth in Cleveland and Oklahoma Counties 10
Table 2. Landuse in the Lake Thunderbird watershed 10
Table 3. Waterbodies in the Lake Thunderbird watershed 12
Table 4. Livestock in Oklahoma and Cleveland Counties 16
Table 5. Possible management practices for urban areas 20
Table 6. Impact of targeted BMPs on phosphorus and chlorophyll­a
23
Table 7. Schedule and load reduction goals 29
Table 8. Interim milestones for Trailwoods project 30
Table 9. Autosampler locations in the Lake Thunderbird Watershed 34
Table 10. OCC analytical parameters and sampling frequency 34
Table 11. Funding for specific projects/efforts 37
LIST OF FIGURES
Figure 1. Lake Thunderbird watershed 7
Figure 2. Municipalities in the Lake Thunderbird watershed 9
Figure 3. Landuse in the Lake Thunderbird watershed 11
Figure 4. Location of highest total phosphorus yields 13
Figure 5. Location of highest sediment yields 14
Figure 6. Percent change in percent impervious area from baseline to build­out
14
Figure 7. Location of permitted total retention lagoons and oil/gas wells …..15
Figure 8. Street design of Trailwoods project and location in watershed 18
Figure 9. Potential wetland development sites 22
Figure 10. Timeline for Trailwoods LID Demonstration Project 31
Figure 11. Location of autosamplers in the Lake Thunderbird watershed 35
Lake Thunderbird WBP June 2010
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­PREFACE
Lake Thunderbird, located in central Oklahoma, is a popular recreational lake as well as
a water supply reservoir for the cities of Norman, Del City, and Midwest City, which
have a combined population of approximately 178,000. Significant taste and odor
problems, linked to eutrophication in the lake, have led to complaints from water users.
According to the Oklahoma Department of Environmental Quality (ODEQ) 2008
Integrated Report, Lake Thunderbird is not supporting its Fish and Wildlife Propagation
(Warm Water Aquatic Community) designated use due to turbidity and low dissolved
oxygen (DO), its Aesthetics use due to color, or its Public Water Supply use due to
chlorophyll­a.
The chlorophyll­a
concentration is approximately three times the water
quality standard required for a sensitive water supply. Other impaired waterbodies in
the watershed include 1) Hog Creek, impaired by turbidity and low DO, 2) West Branch
of Hog Creek, impaired by low DO, 3) Moore Creek, impaired by total dissolved solids
(TDS), 4) Elm Creek, impaired by E. coli, turbidity, and TDS, and 5) East Elm Creek,
impaired by low DO.
Excessive nutrient loading in the watershed, primarily from urban development, has
caused the observed eutrophication in the lake. The Central Oklahoma Master
Conservancy District (COMCD), in cooperation with the Oklahoma Water Resources
Board (OWRB), has been monitoring chlorophyll­a
and nutrient concentrations in the
lake since 2000 and has implemented several management alternatives that have
improved the lake’s algae and chlorophyll problems. However, further action is
necessary to achieve full attainment of designated beneficial uses in the watershed.
The Lake Thunderbird watershed covers 256 square miles (163,840 acres) in
Oklahoma and Cleveland Counties, with the major tributary being the Little River. The
watershed is approximately 60 percent agricultural (mostly pasture) and 40 percent
residential development. Significant, consistent population growth has occurred over
the past 30 years and is expected to continue in the area, with a great deal of pasture
being converted to urban areas. Without a proactive plan to address the potential
impact of this urban expansion, water quality in the area is expected to continue to
decline rapidly.
Based on SWAT model results by Vieux (2007), it is estimated that approximately
18,000 kg of phosphorus enters Lake Thunderbird each year. Nonpoint source (NPS)
pollution associated primarily with increased impervious surfaces due to urban growth
appears to be the primary source of the water quality problems in the Lake Thunderbird
watershed. Modeling of the watershed has resulted in a recommendation of a 58%
percent reduction (about 10,000 kg/yr) of total phosphorus to Lake Thunderbird in order
to produce acceptable water quality conditions (chlorophyll­a
concentration of 10 mg/L or
less) (OWRB 2006). A TMDL is currently being developed by the ODEQ for the lake to
address sediment and dissolved oxygen impairments. Load reduction estimates
resulting from this effort will be added to the watershed plan when the TMDL is
released.
Lake Thunderbird WBP June 2010
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­It
is projected that various low impact development (LID) practices could dramatically
improve the nutrient and sediment loading in the watershed in a relatively short time
frame. The Lake Thunderbird Watershed Based Plan (WBP) refers to the initial
implementation of actions focused on LID, which are necessary to restore beneficial use
support to Lake Thunderbird and its tributaries.
Lake Thunderbird WBP June 2010
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­INTRODUCTION
The Nonpoint Source Program and Grants Guidelines for States and Territories for FY
2004 and Beyond requires a Watershed Based Plan (WBP) to be completed prior to any
implementation efforts using incremental funds. The guidance describes nine key
components to be addressed in a watershed­based
plan, much of which builds from the
strategies outlined in the Watershed Restoration Action Strategy (WRAS). These
components include: 1) identification of causes and sources that will need to be
controlled to achieve load reductions, 2) estimate of load reductions expected from the
management measures described, 3) a description of the management measures that
will need to be implemented to achieve load reductions, 4) an estimate of the amounts
of technical and financial assistance needed, associated costs, and/or the sources or
authorities who will bear responsibility, 5) an information/education component that will
be used to enhance public understanding of the project and encourage early
participation in the overall program, 6) a schedule for implementing the NPS
management measures identified in this plan that is reasonably expeditious, 7) a
description of interim, measurable milestones for determining whether control actions
are being implemented, 8) a set of criteria that can be used to determine whether
loading reductions are being achieved over time and substantial progress is being made
or whether the Watershed Plan or Total Maximum Daily Load (TMDL) needs to be
revised, and 9) a monitoring component to evaluate the effectiveness of the
implementation efforts over time.
In order for the WBP to become an integral part of the entire watershed restoration
program, it must be amenable to revision and update. The Lake Thunderbird WBP has
been developed as a dynamic document that will be revised to incorporate the latest
information, address new strategies, and define new partnerships between watershed
stakeholders. It is anticipated that at least biannual revisions may be necessary and
that the responsibility for such revisions will rest primarily with the Oklahoma
Conservation Commission (OCC), with support from the Oklahoma Department of
Environmental Quality (ODEQ), Office of the Secretary of the Environment (OSE) and
the NPS Working Group. It is understood that the water quality goals and the technical
approach set forth in this WBP may not be comprehensive, so they may be expanded in
the future, especially as ODEQ’s work with the TMDL/WMP is completed. Federal and
state funding allocations for future water quality projects designed to address the Lake
Thunderbird Watershed problems should not be based solely upon their inclusion in this
WBP; rather, the WBP should be considered a focal point for initial planning and
strategy development.
Lake Thunderbird WBP June 2010
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­CAUSES
and SOURCES (element a)
Watershed Characterization
The Lake Thunderbird watershed (HUC 111090203010) covers a 163,840 acre area in
Cleveland and Oklahoma Counties. The principal tributary to Lake Thunderbird is the
Little River, which was impounded by the Bureau of Reclamation to form the lake in
1965. Other tributaries are shown in Figure 1. Designated uses of the dam and the
impounded water are flood control, municipal water supply, recreation, and fish and
wildlife propagation. Designated uses of streams in the watershed include aesthetics,
agriculture, warm water aquatic community (WWAC), industrial and municipal process
and cooling water (I & M), primary body contact recreation (PBCR), public and private
water supply (PPWS), fish consumption, and sensitive water supply (SWS).
Cleveland Co.
Oklahoma Co.
Hog Cr.
Kitchen Cr.
West Elm Cr
Elm Cr.
Little Riv er
Nort h Fork Little
Moore Cr.
Rock Cr.
Dav e Blue Cr.
Clear Cr.
Jim Blue Cr.
West Hog C
L. Stanley Draper
Lake Thunderbird
0 5 10 15 Miles
OSAG E
TEXAS
KAY
ELLIS
BEAV ER
CADD O
CMI AR RO N
LE FLO RE
WO ODS
MCC URTAIN
GRAD Y
KOI WA
ATOKA
GRAN T
CREEK
BRYAN
MAJ OR
DEW EY
BLANI E
HARPE R
CUST E R
PTI T S BURG
CRAIG
IL NC OLN
NOBLE
WA S HTI A
LO GAN
GARV IN
GARFI ELD
TIL LM AN
PAY NE
PUSHM AT AH A
ALFAL FA
CARTE R
LO VE
MAYES
WO ODW AR D
COAL
HUGH ES
AD AI R
COM ANCH E
BECKH AM
TUL SA
GRE E R
CA NAD IA N
JA CKSO N
LA TIM ER
ROG ER MIL LS
STEPHE NS
ROG ERS
CHOC TA W
COTT O N
KNI G FIS HER
MUSK OGE E
DELAW ARE
HASKE L
CHER OKEE
PAW NEE
MCI NTOS H
JE FF ERSO N
NO W ATA
MCC LANI
PONTO T OC
OKLAH OMA
SEQU OYAH
SEMI NOLE
OKM ULGEE
HARM ON
JO HNS TON
OKFUS KEE
OTT AW A
WA G ON ER
MUR RAY
POTT AW ATO MIE
CLEVEL AN D
MARS HAL L
W AS HNI GTO N
Figure 1. Lake Thunderbird watershed.
As a municipal water supply, Lake Thunderbird furnishes raw water for Del City,
Midwest City, and the City of Norman under the authority of the Central Oklahoma
Master Conservancy District (COMCD).
Lake Thunderbird WBP June 2010
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­The
morphologic features of Lake Thunderbird are (OWRB 2002):
Area 5,439 acres
Volume 105,838 acre­feet
Shoreline 96 km
Mean Depth 4.7 m (15.4 ft)
Maximum Depth 17.7 m (58 ft)
Water Supply Yield 21,700 acre­feet/
yr (19.4 mgd)
Mean Monthly Discharge/Outflow 74.5 cfs
All of these values represent a reduction since impoundment in 1966 due to
sedimentation. The overall sedimentation rate was estimated as 393 acre­feet
per year
with a total loss of 13,762 acre­feet,
about 12% higher than originally planned. Most of
the sediment accumulation has occurred in the upper portion of the conservation pool.
The decrease of surface area is mostly due to inflow of large­grained
solids from
tributaries (OWRB 2002).
Although the Lake Thunderbird watershed contains Lake Stanley Draper and its
watershed (Figure 1), this area was removed from modeling analyses since discharges
are not allowed over the spillway. This means that seepage under the dam is the only
way that water from the Lake Stanley Draper watershed could enter Lake Thunderbird.
Since any seepage is minimal, Lake Stanley Draper is not considered a source of
nutrient loading to Lake Thunderbird and will not be shown in any of the other figures.
The Lake Thunderbird watershed is located in the Central Great Plains and Cross
Timbers ecoregions (Woods et al. 2005). The Central Great Plains ecoregion is a
transition area between mixed grass prairie in the west, now primarily a winter wheat
growing region, and forested low mountains in eastern Oklahoma. “Gently sloping
narrow ridgetops are separated by steep slopes bordering drainage ways. Some
stream valleys with nearly level flood plains and large stream terraces exist. Dissected
plains with broad rolling ridgetops and moderately steep valley sides occur. Valleys are
usually narrow with broad flood plains and terraces and hilly dissected plains. There
are rivers with wide flood plains and terraces and small streams with narrow
bottomlands. Rolling plains have a deep mantle of windblown sand and sandy outwash.
Elevation ranges from 1,310 to 2,950 ft (400 to 900 m). Soils include Mollisols and
Alfisols” (McNab and Avers 1994). Predominant vegetation includes bluestem­grama
prairie, sandsage­bluestem
prairie, northern flood plain forests, and buffalo grass.
Precipitation ranges from 20 to 35 inches (500 to 900 mm), and temperature averages
50 to 61 degrees F (10 to 16 degrees C). “Groundwater is abundant in areas
associated with sand and gravel deposits; however, it is scarce and may be mineralized
in areas where shale, sandstone, clay, and limestone are near the surface” (McNab and
Avers 1994).
The Cross Timbers ecoregion “is a region of rolling hills and narrow valleys. The terrain
generally is more complex than other parts of central Oklahoma. Elevation ranges from
330 to 1,300 ft (100 to 400 m). Soils in the Cross Timbers ecoregion are mainly Ustalfs.
Lake Thunderbird WBP June 2010
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­Soils
are deep, well drained, and fine to moderate textured; moisture is limited for use
by vegetation during part of the growing season” (McNab and Avers 1994). Oak­hickory
and oak­hickory­pine
forest and extensive areas of tall grassland with a tree layer
comprise the ecoregion. Forest cover consists of post, live, and blackjack oaks, and
pignut and mockernut hickories. Grasses consist of big and little bluestems, Indian
grass, and sunflower. Precipitation averages 35 to 40 inches (900 to 1,050 mm), and
temperature averages 55 to 63 degrees F (13 to 17 degrees C) (McNab and Avers
1994).
Human Population:
The population in Cleveland County, where the majority of the Lake Thunderbird
watershed is located, is 224,898 (2005 Census). The city of Norman, which comprises
about half of the watershed area (Figure 2), is the largest city in the county, with
approximately 102,000 residents (86% urban). The city of Moore makes up about 8
percent of the watershed area and has a population of nearly 45,000. There has been a
steady increase in Cleveland County’s population since 1960, especially in urban areas
(Table 1).
Figure 2. Municipalities in the Lake Thunderbird watershed (Vieux 2007).
About 38% of the Lake Thunderbird watershed area is located within the Oklahoma City
municipal boundary. In Oklahoma County, the population is 691,266, with 523,303
Lake Thunderbird WBP June 2010
­10
­located
within Oklahoma City (2005 Census). The population in Oklahoma County has
also shown consistent growth (Table 1).
Table 1. Population growth in Cleveland and Oklahoma Counties.
County Parameter 1960 1970 1980 1990 2000
Total population 47,600 81,839 133,173 Cleveland 174,253 208,016
Percent change 71.93% 62.73% 30.85% 19.38%
Oklahoma Total population 439,506 527,717 568,933 599,611 660,448
Percent change 20.07% 7.81% 5.39% 10.15%
Landuse:
As shown in Table 2 and Figure 3, approximately 60 percent of the watershed is
agricultural, with pasture comprising the majority of the agriculture land. Most of the
remainder of the watershed is developed, primarily residential.
Table 2. Landuse in the Lake Thunderbird watershed.
Landuse Percent of Watershed Area
Residential Medium Density 26.00
Residential High Density 0.07
Agricultural – Pasture 53.84
Agricultural­Generic
(parks and open spaces) 7.62
Commercial 0.68
Industrial 1.39
Transportation 4.18
Institutional 1.17
Open Water 5.05
Lake Thunderbird WBP June 2010
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­Figure
3. Landuse in the Lake Thunderbird watershed (Vieux 2007).
Causes
The designated beneficial uses for Lake Thunderbird and its tributaries include
Aesthetics, Agriculture, Warm Water Aquatic Community, Primary Body Contact
Recreation, Public and Private Water Supply, Fish Consumption, Industrial and
Municipal Process and Cooling Water, and, for the lake itself, Sensitive Water Supply.
The impaired designated uses and the causes of non­attainment
of designated uses are
shown in Table 3. Lake Thunderbird is listed in Oklahoma’s Integrated Report as a
Category 5 waterbody with impairment of the fish and wildlife propagation beneficial use
due to excess turbidity and low dissolved oxygen as well as non­attainment
of the public
and private water supply beneficial use due to high chlorophyll­a.
The three streams in
the Thunderbird watershed with enough monitoring data to assess designated beneficial
uses (Hog Creek, Elm Creek, and Moore Creek) are listed as impaired for one or more
assigned uses. It is likely that other streams in the watershed are impaired as well, but
not enough data has existed to make an assessment; for the next reporting cycle, the
OCC will have enough data to assess five additional streams in the watershed (Table
9). The WBP will be updated with the results of that assessment when it is performed.
Lake Thunderbird WBP June 2010
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­Table
3. Waterbodies in the Lake Thunderbird watershed (ODEQ 2008).
Waterbody ID Site Name Impaired Designated Uses Causes of Impairment
OK520810000020_00 Thunderbird Lake Warm Water Aquatic Community
Public and Private Water Supply
turbidity, low DO
chlorophyll­a
OK520810000030_00 Hog Creek Warm Water Aquatic Community turbidity, low DO
OK520810000040_00 West Hog Creek Warm Water Aquatic Community low DO
OK520810000050_00 Clear Creek *
OK520810000060_00 Dave Blue Creek *
OK520810000070_00 Jim Blue Creek *
OK520810000080_00 Little River *
OK520810000090_00 Rock Creek *
OK520810000100_00 Elm Creek
Primary Body Contact Recreation
Warm Water Aquatic Community
Agriculture
E. coli
turbidity
total dissolved solids
OK520810000110_00 East Elm Creek Warm Water Aquatic Community low DO
OK520810000120_00 East Elm Creek *
OK520810000140_00 West Elm Creek *
OK520810000150_00 Kitchen Creek *
OK520810000160_00 Kitchen Lake *
OK520810000170_00 North Fork Little River *
OK520810000175_00 Moore Creek Agriculture total dissolved solids
OK520810000180_00 Mussel Shoals Lake Creek *
OK520810000190_00 Mussel Shoals Lake *
*insufficient information or not assessed
Oklahoma Water Resources Board (OWRB) studies on Lake Thunderbird have shown
that chlorophyll­a
levels are high, thus indicative of the excessive algae growth causing
taste and odor problems for the City of Norman water supply. In 2000, over one­half
of
the water samples collected by the OWRB had chlorophyll­a
concentrations greater
than 20 μg/L (OWRB 2003). The chlorophyll­a
concentration was reduced in 2002, after
aeration of the lake ceased, but the lake still had chlorophyll­a
levels high enough to
cause eutrophication. BUMP data collected from 2001­2003
showed an average
chlorophyll­a
concentration of 30.8 μg/L.
Algae species which are known to cause taste and odor problems in drinking water are
present in the lake, and two potentially toxic algae have been noted in Lake Thunderbird
as well. The concentrations of these algae in the lake corresponded to a low to
moderate risk from direct exposure or accidental ingestion in 2001 and low risk in 2002.
This risk was for recreational exposure, with no evidence of risk noted for water supply
(OWRB 2003). Reducing the amount of nutrients entering the lake is necessary to
decrease the algal concentrations.
Sources
There are no point sources in the Lake Thunderbird watershed; hence, nonpoint
sources are the primary contributors to the pollution problems in this watershed.
Nonpoint sources are those which supply pollutants to surface water diffusely, rather
than as a definite, measurable quantity at a single location. These sources typically
Lake Thunderbird WBP June 2010
­13
­involve
land activities that contribute bacteria, sediment, and/or nutrients to surface
water as a result of runoff during and following rainfall.
Urban Land Use:
The primary sources of pollution in the Lake Thunderbird watershed are associated with
urban expansion and the accompanying development. As urbanization progresses,
runoff from impermeable surfaces and from construction areas (both housing
developments and road construction) are increasingly contributing to nutrient and
sediment loading from the watershed. Water quality is being severely impacted by
increasing runoff volume and velocities, which cause increased erosion of streambanks,
destruction of instream and riparian habitat, and siltation, as well as increased nutrient
loads. Improper use of fertilizers or over­fertilization
may increase with the expected
population growth in the watershed and contribute to the pollution of lakes and
groundwater through loading of soluble and particulate phosphorus as well as nitrogen.
Bacteria and nutrients from domestic pets will be expected to increase as well with the
expected increase in population growth. According to Vieux (2007), urban runoff should
be considered as an increasing, highly significant nonpoint source of pollution in this
watershed.
Vieux and associates performed a study in the Rock Creek watershed, a tributary to
Lake Thunderbird (COMCD 2006). Based on monitoring and analysis of water quality
data in Rock Creek, it was determined that a higher level of nutrients was found in
runoff from developed versus undeveloped land. Vieux’s modeling efforts of the entire
Lake Thunderbird watershed in 2007 supported this finding, indicating that the areas of
the watershed contributing the greatest phosphorus (the limiting nutrient of the lake)
load per unit area were the highly urbanized areas of Moore and Oklahoma City, as well
as a small portion of Norman immediately north of the lake (Figure 4).
Figure 4. Location of total phosphorus sources and yields (kg/hectare) in the
Lake Thunderbird Watershed as determined from SWAT modeling (Vieux 2007).
Lake Thunderbird WBP June 2010
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­Similarly,
the greatest sediment load is coming from Moore and the west side of
Norman, followed by the Oklahoma City area (Figure 5).
Figure 5. Location of sediment sources and yields (kg/hectare) in the
Lake Thunderbird Watershed as determined from SWAT modeling (Vieux 2007).
The Rock Creek study (COMCD 2006) indicated that the greater loading of nutrients
from developed areas was due to increased impervious surface and increased
fertilization in urban areas. Vieux’s 2007 SWAT modeling also suggested that
imperviousness was a key factor affecting loading rates in the watershed. It is expected
that continued conversion of agricultural land to residential land will more than double
the phosphorus load to the lake, increasing from an average of 25 kg/ha currently to 54
kg/ha in the future (assuming a build­out
scenario with conversion of 50% of agricultural
areas to residential). Figure 6 shows the areas which are expected to experience the
greatest increases in impervious surface under a build­out
scenario.
Figure 6. Percent change in impervious area from baseline (current levels) to build­out
(projected
conversion of 50% of agricultural lands to residential) (Vieux 2007).
Lake Thunderbird WBP June 2010
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­Based
on Vieux’s SWAT model calculations, the total average phosphorus load to Lake
Thunderbird is between 18,000 kg/yr and 23,000 kg/yr. According to Figure 4, the
highest phosphorus loading is occurring in the watersheds of the North Fork of the Little
River and Moore Creek on the west side of the lake, as well as Hog Creek on the east
side of the Thunderbird watershed. The Moore and Norman areas on the west side of
the watershed are contributing the highest sediment load, especially in the headwaters
of Little River, the North Fork of the Little River, Moore Creek, and Rock Creek (Figure
5).
While there are no point source discharges in the Lake Thunderbird watershed,
“bypass­discharges”
from municipalities may occur due to overflows or sewer main
breaks. Several of these events have occurred within the watershed. For example,
from June 2004 to August 2006, the sum of these discharges was:
City of Moore 59,930 gallons discharged to Little River
City of Norman 44,483 gallons discharged to Little River
According to Vieux (2007), raw sewage contains approximately 4­15
mg/L of water­soluble
phosphorus, equating to 2­5
kg of phosphorus over that two year period. This is
not considered a significant amount relative to the overall phosphorus entering the
watershed. The City of Norman completed a wastewater treatment plant (WWTP)
upgrade in March 2010, which should reduce the number of failures in the future. The
hydraulic capacity of the plant has increased from 45,000m³ a day to nearly 100,000m³
a day.
Permitted Sources:
Nonpoint source permitted
activities within the watershed
include 12 total retention lagoons
(Figure 7). Total retention lagoons
hold solid and liquid wastes prior to
land application and may leak or
overflow, thus affecting water
quality.
In addition, there are over 300 oil
and gas permits in the watershed,
located on approximately every
section in the watershed. Not all of
the permitted wells are active;
however, oil and gas operations
could be a potential source of high
TDS values as well as turbidity
sources.
Figure 7. Location of permitted total
retention lagoons and oil/gas wells.
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# Total Retention Lagoons
$ Oil and Gas Wells
Lake Thunderbird WBP June 2010
­16
­Rural
Land Use:
Pasture/forage land is the prevalent rural land use in the watershed. Cattle are the
dominant animal industry in Oklahoma and Cleveland Counties (Table 4). Livestock
grazing in pastures deposit manure, making it possible for the nutrients and bacteria to
enter surface water with runoff. In addition, livestock often have direct access to
waterbodies providing a concentrated source of loading directly into streams. Animals
loafing in the stream also contribute to turbidity problems by stirring up sediment, and
their travels to and from the stream erode banks and carve trails which serve as direct
conduits for NPS contribution during runoff events.
Table 4. Livestock in Oklahoma and Cleveland Counties (USDA Census 2002).
Livestock County Number of animals
Cattle and calves OClkelavheolamnda 2216,,592825
Horses and ponies OClkelavheolamnda 34,,034800
Layers 20 weeks old and older OClkelavheolamnda 12,,472748
Hogs and pigs Cleveland 2,267
Goats Oklahoma 1,696
Sheep and lambs Oklahoma 1,402
Despite the large number of animals, particularly cattle, in these counties, agriculture in
the Lake Thunderbird watershed is largely in the form of small, urban ranchettes, where
landowners have 5­20
acres to keep a few horses or a small herd of cattle. Preliminary
results from Vieux (2007) suggest that, although these areas contribute to overall
loading, urban sources dominate.
Septic Systems:
Failing septic systems can contribute to pathogen and nutrient problems in both
groundwater and surface waters if leakage or illicit discharge occurs. Any loading of
bacteria into the groundwater can enter surface water through seeps or springs. Failing
septic systems were not likely to be a significant factor in this watershed due to the low
density of septic systems.
Wildlife:
Wild animals which produce fecal bacteria and have direct access to streams include
deer, raccoons, other small mammals, and avian species. Wildlife is considered to be a
minor contributor of pollution in this watershed.
Shoreline / Streambank Erosion:
Lake Thunderbird is experiencing considerable shoreline erosion with cut banks
exceeding 20 feet in height in some locations (OWRB 2001a). Wave action and runoff
on these bare areas are contributing significantly to the turbidity impairment of the lake.
A shoreline erosion control demonstration project was intiated by the OWRB in order to
reduce the amount of suspended sediment in Lake Thunderbird. During 2003, the
OWRB staff installed hundreds of feet of breakwater structures and more than 1,000
aquatic plants along a 450­foot
area of the southern shoreline. It is expected that the
Lake Thunderbird WBP June 2010
­17
­breakwaters
will help settle out sediments and
promote the establishment of beneficial
shoreline vegetation. In addition, the OCC in
partnership with the City of Norman is currently
implementing a project to restore a riparian
buffer along the North Fork of the Little River.
Unstable streambanks could also contribute
significantly to phosphorus loading in the
watershed, especially since streambank soils
are often high in phosphorus.
Lake Thunderbird shoreline erosion control
LOAD REDUCTIONS (element b)
Because of Lake Thunderbird’s impaired status, Total Maximum Daily Load (TMDL)
allocations are required for dissolved oxygen and turbidity. The Oklahoma Department
of Environmental Quality Water Quality Division (ODEQ) is currently working on a
detailed Hydrological Simulation Program Fortran (HSPF) model for the watershed and
has contracted to have an EFDC in­lake
model developed. These two models will be
used to develop a comprehensive TMDL for the lake. Until the release of the TMDL, the
focus of this WBP will be on reducing phosphorus, since data collected and analyzed by
the OWRB indicates that phosphorus is the limiting nutrient in Lake Thunderbird. The
subwatersheds in red in Figure 4 will be the primary targets for implementation projects
since these are the areas supplying the highest phosphorus loads and, thus, should
provide the largest load reductions.
Using a SWAT model, Vieux (2007) calculated that the total average phosphorus load
to Lake Thunderbird is between 18,000 kg/yr and 23,000 kg/yr. This correlates with a
measured average total phosphorus concentration of 0.057 mg/L and chlorophyll­a
concentration of 30.8 mg/L. The primary source of phosphorus loading in the watershed
is urbanization, as shown in Figure 4 and discussed in the previous section. Runoff
from impervious surfaces in urban areas has the highest potential for contributing
pollutants to waterbodies in these areas.
The goal of this WBP is to reduce the nutrient loading to Lake Thunderbird so that the
chlorophyll­a
concentration is 10 mg/L, a 32% reduction. This corresponds to a
reduction of approximately 10,000 kg/yr total phosphorus (58% overall) (Vieux 2007).
This reduction in phosphorus should increase the dissolved oxygen concentration of the
lake, decrease the turbidity, and allow restoration of the WWAC designated use. In
addition, it is expected that measures implemented through this watershed project to
address phosphorus will concomitantly reduce the bacteria loading in Elm Creek and
sediment loading in Moore Creek. However, urbanization is expected to continue in this
watershed, so it is vital to examine the required load reductions in light of future
development plans.
Lake Thunderbird WBP June 2010
­18
­Vieux
(2007) modeled the loads expected if 50% of the agricultural or vacant land was
converted to residential property over the next 30 years. The findings indicate that the
total phosphorus load would be 24,907 kg/yr under these conditions, so a reduction of
approximately 68% (approximately 16,937 kg/yr) would be necessary to achieve the
chlorophyll­a
goal of 10 mg/L in the future. This reduction will be the long­term
goal for
the project.
The following section of the WBP addresses the management measures necessary to
achieve these present (short­term)
and future (build­out)
load reductions. After the
release of the TMDL for Lake Thunderbird, most likely in 2011, management measures
and load reduction goals described in this WBP will be updated based on the
recommendations of the TMDL.
NPS MANAGEMENT MEASURES (element c)
SWAT modeling has allowed for estimation of nutrient load reductions expected from
certain management measures (Vieux 2007). The results of this modeling effort show
that Best Management Practices (BMPs) should focus on reduction of nutrient loading
from urban nonpoint sources. Implementation of such practices is expected to achieve
an initial NPS phosphorus load reduction goal of 58% and is likely to significantly
improve the turbidity, bacteria, and dissolved oxygen issues in the lake and streams.
It is recognized that not any one activity could realistically result in the required
reduction; instead, numerous strategies will have to work together to achieve the
desired result. With this in mind, this document is not intended as a final, static plan,
but rather one that will be updated as needed to reflect new information, resources, and
necessary adjustments in implementation strategy.
The initial watershed implementation program will focus on
facilitating Low Impact Development (LID) techniques in the
watershed. A local developer has partnered with OCC to
implement and assess LID practices in a new residential
development, titled the Trailwoods Project. For this project, 18
houses will be built along a street with rain gardens to filter
stormwater runoff from the street (dark green in Figure 8) while 18
houses will be built
on an adjoining
street with
conventional curbs
and street gutters to
convey stormwater.
The OCC will install
autosamplers for
continual monitoring
and assessment of
Figure 8. Street design (LID side) of Trailwoods project (left), and
location of the neighborhood in the watershed (right).
Lake Thunderbird WBP June 2010
­19
­the
runoff of both streets. This project will be primarily a demonstration and research
project. Results will be presented to City of Norman officials in the hope that more
projects like this will be approved.
Before more broad­reaching
projects can be tackled, a significant portion of the
implementation strategy will be to work with cities in the watershed to revise their
building codes as needed to allow for construction of LID systems. Special approval
was granted for the Trailwoods project from the City of Norman. OCC will compile and
review examples of existing codes from nearby communities that support LID and
provide for water quality friendly construction techniques. These examples will be
presented to the watershed cities for possible incorporation into their municipal codes.
In addition, OCC will send city planners from the area to LID workshops and related
training such as the one offered by the Water Conservation Resource Center in
Fayetteville, Arkansas. OCC will also organize and facilitate tours of LID
implementation in nearby areas to demonstrate possibilities for the city planners and
relevant personnel. Since most of the project area is incorporated and zoned, the OCC
will also work with municipalities to achieve pollution control through zoning and
ordinance regulations.
Vieux’s modeling results clearly indicate the subwatersheds contributing the greatest
loads currently, as well as those where the greatest future load is expected (Figures 4,
5, and 6). These urban areas of the watershed will be targeted for the initial
demonstration of low­impact
development (LID) so that the most efficient load
reductions can be accomplished. Examples of urban practices that will be suggested
are given in Table 5. The efficiency of each of these practices in removing phosphorus
is included in the table, as well as the practical application and constraints associated
with each practice. Combining certain types of practices and implementing them
throughout the watershed could result in reductions in total phosphorus load beyond the
required reduction to meet the chlorophyll­a
goal of 10 mg/L (Vieux 2007). Initial
implementation will be focused in the subwatersheds with the highest phosphorus
loading (Figure 4). As mentioned previously, these areas are the most developed and
actively developing areas in the watershed, so it will be vital to work with officials from
Norman, Moore, and Oklahoma City to get approval for LID implementation.
An additional strategy for in­lake
reduction in
sediment and nutrient loads would be to work with
management authorities to institute new/amended
boat traffic limitations. Because of its proximity to
the urban community, Lake Thunderbird
experiences particularly heavy powered boat traffic,
which is thought to contribute significantly to
shoreline erosion and thus nonpoint delivery of
sediment and nutrients. Lake­wide
limitations on
engine size and/or speed restrictions could aid in
reducing this problem.
Urban raingarden
Lake Thunderbird WBP June 2010
­20
­Table
5. Possible management practices for urban areas. Highlighted rows are practices recommended for this project by Vieux (2007).
Best
Management
Practice
Phosphorus
Removal
Efficiency
Maintenance Required Other Benefits Problems Applicable Landuse
Conditions
Sediment
Forbay
Required to
achieve
Phosphorus
removal efficiency
for structural
practices.
Sediment should be removed every 3­5
years or when 6­12
inches have accumulated, whichever occurs first. To
reduce maintenance costs, an on­site
sediment disposal
area should be included in the design.
Improves phosphorus and sediment removal
efficiency of primary MPs. Facilitates
maintenance of MPs and extends the "life
expectancy" of primary management practice.
Phosphorous removal efficiencies are
based on the inclusion of sediment forbays
in the project design.
Required to improve efficiency and life span
of most other management practices. Also
facilitates maintenance of other
management practices.
Vegetated
Filter Strip 10%
Requires regular maintenance. This management
practice usually has short life span due to lack of
maintenance, improper location, and poor vegetative
cover. Maintenance includes inspections, fertilizing,
watering, and re­planting.
Also repair from gully erosion,
traffic, and concentrated flow. After established (several
years), maintenance requires removal of accumulated
sediment, reestablishing vegetations, weeding invasive
weeds, pruning woody growth.
May also result in reduction of nitrogen in
storm water.
For Overland Sheet Flow!!! Max
contributing area 5 acres. From Center for
Watershed Protection (1996), runoff
changes from sheet flow to concentrated
flow after traveling 75 feet on impervious
surfaces and 150 on pervious surfaces.
Requires soils with infiltration rate of 0.52
in/hr (sand and sandy loams).
Residential (16­21%)
impervious or as a
pretreatment component to structural
management practices.
Grassed
Swale 15% Maintain thick vegetation at 3­6
inches. Remove debris,
and sediment, and re­establish
vegetation if needed.
Excellent for residential areas. Requires
matenance agreements included in land titles.
Maintenance responsibility of each land owner.
(Monograph 14, pg 400) ­Cost
effective
compared to concrete gutters and efficient
sediment removal.
Landowners are likely to mow the grass in
the swale too short reducing pollutant
removal efficiency. Requires soils with
infiltration rates of 0.27 in/hr (silty loams) or
better.
Residential 16­21%
impervious cover. If
water quality swales are incorporated, will
work with higher density development up to
37% impervious area.
10% with
voluntary reduction
May be difficult to obtain "buy­in"
from the
community. Requ Urban ires annual soil testing.
Nutrient
Management Up to 22% with
statutory reduction
Urban nutrient management involves the reduction of
fertilizer (especially phosphorus) to grass lawns and other
urban areas. Implementation of urban nutrient
management is based on public education and
awareness, with emphasis on reducing excessive fertilizer
use.
May also result in reduction of nitrogen in
storm water. Requires implementing an ordinance such
as the Minnesota Phosphorus Lawn
Fertilizer Law.
Percent impervious cover 16­21%.
Constructed
Wetlands
30%
Second season reinforcement plantings are often
needed. Mow biannually to reduce woody growth on outer
boundary. Maintain sediment forbay. Pretreatment
management practices will reduce the cost of
maintenance and the effective life expectancy of the
constructed wetland. Remove sediment from forbay every
3­5
years or when 6­12
inches of sediment has
accumulated.
High removal rate of particulate and soluble
pollutants (nutrients) and sediment. Wildlife
preservation. Bird watching.
Permeable soils are not suited for
wetlands construction. Requires large land
areas (2% of the size of the contributing
watershed).
Percent impervious cover 22­37%.
Basin
requires minimum drainage of 10 acres and
may not be located near (within 100 feet) of
septic systems. Permeable soils are not
suited for constructed wetlands. May not be
suited for highly visible sites or adjacent to
highly manicured sites.
Extended
Detention
Basin
(2xWQ Vol)
35%
Mow 2x's per year; remove debris from spill way and
trash rack at control structure; and maintain sediment
forbay.
Excellent option for watershed approach.
Function as designed for long periods without
routine maintenance.
Not aesthetically pleasing. Requires 20
foot vegetative buffer. Drainage areas over
50­75
acres require provisions for base
flow. Not suitable for highly permeable
soils.
Percent impervious cover 22­37%.
Low
visibility sites. Appropriate for regional or
watershed approach.
Extended
Detention­Enhanced
50%
Mow two times per year; remove debris from spill way
and trash rack at control structure; and maintain sediment
forbay.
The enhanced extended detention basin has a
shallow marsh which provides additional
pollutant removal and reduces re­suspension
of
settled pollutants. To increase the phosphorus
removal of the extended detention basin one
must increase the volume of the marsh. Wildlife
habitat and associated recreation.
Not aesthetically pleasing. Requires a 20
foot vegetative buffer. Drainage areas over
50­75
acres require provisions for base
flow. Not suitable for highly permeable
soils.
Percent impervious cover 38­66%.
Lake Thunderbird WBP June 2010
­21
­Best
Management
Practice
Phosphorus
Removal
Efficiency
Maintenance Required Other Benefits Problems Applicable Landuse
Conditions
Retention
Basin I
(3XWQ Vol)
40%
Mow two times per year; remove debris from spill way
and trash rack at control structure; maintain sediment
forbay. Aeration may be needed in Oklahoma.
High nutrient, sediment and phosphorous
removal efficiencies. Can help with flood control
and downstream channel erosion when
coordinated within a Watershed Management
Plan.
Increase water table. Needs to be part of
"watershed management plan" as too many
detention/retention basins in a basin can
severely alter the natural flow conditions
with combined peak flows and increased
flow durations, resulting in downstream
flooding and stream channel degradation.
Percent impervious cover 22­37%.
Basin
requires minimum drainage of 10 acres and
not located near (within 100 feet) of septic
systems. Permeable soils are not suited for
retention basins.
Retention
Basin II
(4xWQ Vol)
50%
Mow two times per year; remove debris from spill way
and trash rack at control structure; maintain sediment
forbay. Aeration may be needed in Oklahoma.
High nutrient, sediment and phosphorous
removal efficiencies. Can help with flood control
and downstream channel erosion when
coordinated within a Watershed Management
Plan.
Increase water table. Needs to be part of
"watershed management plan" as too many
detention/retention basins in a basin can
severely alter the natural flow conditions
with combined peak flows and increased
flow durations, resulting in downstream
flooding and stream channel degradation.
Percent impervious cover 22­37%.
Basin
requires minimum drainage of 10 acres and
not located near (within 100 feet) of septic
systems. Permeable soils are not suited for
retention basins.
Retention
Basin III
(4xWQ Vol
with aquatic
bench)
65%
Mow two times per year; remove debris from spill way
and trash rack at control structure; maintain sediment
forbay. Aeration may be needed in Oklahoma.
High nutrient, sediment and phosphorous
removal efficiencies. Can help with flood control
and downstream channel erosion when
coordinated within a Watershed Management
Plan.
Increase water table. Needs to be part of
"watershed management plan" as too many
detention/retention basins in a basin can
severely alter the natural flow conditions
with combined peak flows and increased
flow durations, resulting in downstream
flooding and stream channel degradation.
Percent impervious cover 22­37%.
Basin
requires minimum drainage of 10 acres and
not located near (within 100 feet) of septic
systems. Permeable soils are not suited for
retention basins.
Bioretention
basin or
Rain
Gardens
50%
Annual soil pH testing and application of lime to adjust
pH; routine mulching and maintenance of plant material.
Removal of hazardous and toxic soil/plant material
required when the system "dies".
Degradation of oily pollutants, clay absorbs
heavy metals, nutrients and hydrocarbons.
Reduce peak discharge and provides
groundwater recharge. Accumulation of toxins
and heavy metals within 5 years.
Requires permeable soil! Life expectancy
as little as 5 years. May require removal of
infiltration media and plant material.
Percent impervious cover 38­66%.
Highly
visible development. Residential to fairly
high density commercial projects.
Bioretention
filter
50%
Annual soil pH testing and application of lime to adjust
pH; routine mulching and maintenance of plant material.
Removal of hazardous and toxic soil/plant material
required when the system "dies".
Filter is connected to storm sewer which can
lead to structural or other primary management
practices.
Requires permeable soil. Life expectancy
as little as 5 years. May require removal of
infiltration media and plant material when
the system dies. This material may be
classified as hazardous or toxic upon
removal.
Percent impervious cover 38­66%.
Infiltration
(1 x WQ Vol) 50%
Inspection monthly and after large storm events until
operations are stable. After the system is stable, inspect
semi­annually
and after large storm events. Control
sediment and maintain vegetation.
Reduce peak discharge and provide
groundwater recharge
Does not control large volumes of run­off,
works for 2­year
design storm. Requires
permeable soil and lower water table. Does
not work for oily sites due to clogging from
sediment, oil, and grease.
Percent impervious cover 38­66%.
Not
suitable for roadways, parking lots and car
service facilities unless a settling basin or
"cell" is used for pretreatment.
Infiltration
(2xWQ Vol) 65%
Inspection monthly and after large storm events until
operations are stable. After the system is stable, inspect
semi­annually
and after large storm events. Control
sediment and maintain vegetation.
Reduce peak discharge and provide
groundwater recharge
Does not control large volumes of run­off,
works for 2­year
design storm. Requires
permeable soil and lower water table. Does
not work for oily sites due to clogging from
sediment, oil, and grease.
Percent impervious cover 38­66%.
Not
suitable for roadways, parking lots and car
service facilities unless a settling basin or
"cell" is used for pretreatment.
Sand Filter 65%
Properly sized filters have a life span of up to 20 years.
However, the top few inches of sand needs to be replaced
every 3­5
years. Requires accessibility (manholes) for
vacuum trucks.
Removal of heavy metals, BOD, nutrients, and
hydrocarbons. Aerobic filters enriched with iron
may attain nearly complete removal of
phosphorus. Can be placed underground.
Subject to failure by clogging by sediment
and heavy hydrocarbon loads.
Underground vaults are classified by OSHA
confined spaces. Will not function properly
if subjected to continuous or frequent flows.
Essential to exclude flow containing
chlorine (such as pool water).
Ultra­urban
settings with percent impervious
cover 67­100%.
Suited for high pollutant
removal on medium to high density
development. Not suitable for basins with
high sediment loads due to clogging.
Lake Thunderbird WBP June 2010
­22
­Vieux
(2007) found that the Little River Arm of
Lake Thunderbird reduced the phosphorus load
to the main body of the lake by 36% by allowing
sediment and the phosphorus bound to it to
settle as the water velocity decreases upon
entering this area. It is possible that increasing
the residence time of sediment in shallow arms
of the lake such as this may significantly
improve water quality. One of the tasks in the
current OCC project will be to create a wetland
development plan for the Upper Little River
(above the bridge) and Hog Creek arms to
promote more extensive settling of sediment
and associated nutrients before entering the lake Figure 9. Potential wetland development
(Figure 8). sites.
The City of Norman has recently completed a 682 page, comprehensive “Storm Water
Master Plan” (SWMP) which considers issues such as water quality, creek corridor
environmental features, creek erosion / stabilization, and greenbelt / open space
expansion opportunities at a very detailed subwatershed level. One of the goals of the
plan is “to protect natural creek riparian environments, as well as comprehensively
managing floodplains to include recreational opportunities, trails and open spaces”
(Cole 2007). This document describes 12 subwatersheds in great detail, including
proposed BMPs to address problems causing flooding and stream erosion. The
establishment and expansion of riparian buffers is one of the top recommendations for
improving water quality and addressing flooding in the city. The City of Norman realizes
that the restoration of the bottomland
hardwood forest and riparian wetlands that
once were widespread along the Little River
and its tributaries could improve overall
quality of the lake. In addition, streambank
stabilization projects and LID are to be
encouraged. The OCC is currently
cooperating with the City in a streambank
stabilization project and hopes to participate
in the development of different aspects of the
larger SWMP. The entire SWMP may be
viewed at this link:
http://www.ci.norman.ok.us/sites/default/files/WebFM/Norman/Public%20Works/Storm
WaterMasterPlanFinalDraft.pdf
Oversight of OCC project activities will be the responsibility of the Project Coordinator
with assistance from the City of Norman, the Cleveland County Conservation District,
and additional OCC staff. This WBP will be presented to cities, developers, and other
appropriate groups in the watershed in an attempt to further the adoption of these
practices. Activities in the watershed will be designed to complement projects that the
Cleveland Co.
Oklahoma Co.
Hog Cr.
Kitchen Cr .
West Elm Cr
Elm Cr.
Little Riv e r
North F ork Lit tle
M oore Cr.
Rock Cr.
Dav e B lue Cr.
Clear Cr.
Jim Blue Cr.
West Hog C
L. Stanley Draper
Lake Thunderbird
0 5
Proposed wetland
development
sites
Little River in Norman
Lake Thunderbird WBP June 2010
­23
­cities
have planned, for example, those detailed in the City of Norman SWMP.
Soil tests may be offered as part of this project in order to reduce nutrients in runoff from
lawns, gardens, parks, and golf courses in the watershed. The average soil test
phosphorus (STP) level of lawn and garden soils in Oklahoma is several times higher
than that required by plants. This suggests that too much fertilizer and/or incorrect
fertilizer formulas are being used for those areas. Studies have shown that dissolved
reactive phosphorus (which is linked to algae blooms directly) in the runoff from lawn
and golf courses increases as STP and fertilizer rates increase. Education efforts will
be tied to soil test results so that proper fertilizer application is emphasized.
Vieux modeled several combinations of BMPs that would result in the necessary
reduction in total phosphorus (TP) loading to achieve a chlorophyll­a
concentration
below 10mg/L. As shown in Table 6, below, constructing wetlands and installing some
structural controls would reduce TP loading by 66%, and if coupled with fertilizer
reductions, these BMPs are expected to result in the appropriate decrease in TP and,
subsequently, chlorophyll­a.
Table 6. Impact of targeted BMPs on percent reduction of total phosphorus (TP), TP loads, TP
concentration, and chlorophyll­a
concentration.
The small acreage size managed by the typical agricultural producer, coupled with the
respectively large number of small landowners, adds to the difficulty of significantly
reducing loads from agricultural areas in this watershed. In the future projects,
agricultural BMPs may be funded, including: (1) riparian area establishment to include
fencing, vegetative establishment, off­site
watering, livestock shelters and incentive
payments; (2) streambank stabilization to include fencing and vegetative plantings; (3)
animal waste storage facilities / heavy use areas; and (4) pasture management /
pasture establishment. Cooperation with NRCS in Cleveland and Oklahoma Counties
may allow expansion of EQIP and CSP programs (CSP began in 2005 in this area as
part of the Little River priority watershed) which include practices to reduce soil erosion
and improve livestock watering facilities.
The OWRB conducted a shoreline erosion control demonstration project at Lake
Thunderbird through EPA’s §319 NPS program. Depending on the success of this
project, other similar projects may be implemented in the lake to reduce lake margin
Lake Thunderbird WBP June 2010
­24
­sediment
contributions. Through this project, the OWRB seeks to educate lake
managers on the benefits of establishing aquatic plants to improve the health of the
aquatic community and reduce erosion.
In addition, the OWRB and COMCD have partnered to install an aeration system in the
lake to increase the dissolved oxygen and improve overall water quality. The project
will withdraw water from the lake bottom, oxygenate it to 300% (310 mg/l), and return
the supersaturated water back into the lower lake layer, restoring the dissolved oxygen
to levels that will allow attainment of the designated uses and reduce summer
chlorophyll­a
levels. Funding ($692,773) for this effort was derived from the Oklahoma
Water Resources Board’s Clean Water State Revolving Fund obtained through the
American Recovery and Reinvestment Act of 2009. The aerator is scheduled to begin
operating in the summer of 2010.
BMPs, planned and implemented, will be tracked for future watershed modeling and for
reporting project performance. Project staff will make regular site visits to assess
progress in implementing planned BMPs. Details will be summarized in the project final
report.
PUBLIC OUTREACH (element e)
Much of the initial focus of the WBP will involve educating personnel and changing city
ordinances. This section identifies agencies, organizations, and services that are
already active in the watershed or that will be collaborators in the Lake Thunderbird
watershed. These groups will help develop the WBP and assist in other planning efforts
in the watershed to varying degrees. Cooperation and implementation by cities in the
watershed is imperative to achieve the water quality improvement goals.
The specific roles of the groups and programs which are likely to contribute to the public
outreach efforts in the Lake Thunderbird Watershed are summarized in no particular
order below:
1. Local Conservation District Offices
The Cleveland County Conservation District will provide substantial support for
the implementation of this project. The Oklahoma County Conservation District
will also provide support for the project, but to a lesser degree than Cleveland
County due to difference in district area in the watershed. The Districts may
participate in educational activities such as seminars, training sessions, and
meetings to interact with local people and provide technical assistance and
information.
2. Municipalities
Cities in the watershed maintain active, well­developed
education programs.
However, education programs are rarely funded to a level that meets existing
needs and can always use additional technical support and other resources. The
Lake Thunderbird WBP June 2010
­25
­Lake
Thunderbird education program will supplement rather than replace the
existing education programs in the watershed in cooperation with local
stakeholders. The City of Norman specifically plans to establish a program to
educate residents about fertilizer usage.
3. OCC Education Programs
The education component of the Lake Thunderbird Watershed Implementation
Project will be developed around the following goals:
(1) Work within the MS4 coordinators of Moore, Norman, and Oklahoma City to
assist their programs with NPS pollution education.
(2) Educate city staff about low impact development, nonpoint source pollution,
water quality, and water conservation.
(3) Involve cities and residents in the targeted areas in education programs
designed to explain the water quality problems and what can be done to
reduce potential impacts.
(4) Write frequent articles for area newsletters and/or newspapers about project
activities.
(5) Work with Conservation Districts on a Blue Thumb program in the watershed.
(6) Develop a display for the project that can be used to educate the public on
the 319 Program. Display should include basic information on the program,
its cooperators, and contact people of ongoing programs in the watershed.
(7) Track how participation in the education program has changed people’s
behaviors. Project coordinator will follow five to ten percent of people
intercepted through different aspects of this and related project activities and
will contact them on an annual basis throughout the project period to
determine whether they have made any changes that would affect NPS
pollution.
(8) Plan and conduct educational meetings to include: tours, earth days, fairs,
etc. These education programs will be designed to explain the water quality
problems and what can be done to reduce potential impacts, both agricultural
and urban.
(9) Coordinate education of public on nutrient management and water quality
through the Master Gardener Programs of Oklahoma and Cleveland
Counties. Master Gardeners will be educated on water quality issues and
technologies. They will participate in the bioretention cell program by helping
to evaluate the performance of vegetation in the rain gardens and by
explaining their performance to the public. The Master Gardeners will also
conduct demonstrations for the public at visible locations and at public
functions like the County Fair and other events.
Initially, the OCC will organize and hold one regional LID workshop through the Institute
for Quality Communities. This will allow for in­depth
education on stormwater BMPs
and allow civic officials training in Oklahoma and the south­central
plains region. The
OCC will provide educational programs as part of other projects in the watershed as
well. For instance, as part of a 2003 Riparian Area Restoration project, three seminars,
targeted at City planners, local officials, and students of various ages, will be held to
Lake Thunderbird WBP June 2010
­26
­relate
the importance of riparian wetland areas within urban and rural environments.
Demonstration of riparian management practices will also be part of the education
program for this project.
In general, youth education is a significant effort that will be pursued in the Lake
Thunderbird watershed. Most youth education activities focus on general water quality
maintenance and improvement and include activities such as 4­H
group water quality
monitoring and education, “Earth­Day­Every­Day”
activities fair where hundreds of
elementary school children and some of their parents are exposed to environmental
education, and various other training sessions. Blue Thumb educators will play an
important role in youth education in this watershed.
The success of water quality protection programs in the watershed depends on the
approval and cooperation of the local landowners and various government agencies. In
summary, public outreach to assure support of this and future evolutions the Watershed
Based Plan will come from:
· Regular media coverage of activities/issues (both at local and State levels).
· Education programs that involve segments of the community ranging from school
children to agricultural producers to homeowners.
· Programs that encourage local citizens to experience “ownership and
understanding” of environmental issues such as volunteer monitoring, clean­up
events, and other educational grassroots efforts to address the problem.
The goal of the public outreach portion of this project is to develop a program that will
help the citizens of the Lake Thunderbird Watershed reduce NPS pollution.
CRITERIA to DETERMINE PROGRESS (element h)
The ultimate goal of this WBP is to reduce the nutrient loading to Lake Thunderbird by
approximately 10,000 kg total phosphorus per year, as well as reduce the pathogen and
sediment loads in the tributaries to the lake, so that all designated uses of waterbodies
in the watershed are fully attained. These goals are guided by the water quality criteria
described in this section, all of which are based on Oklahoma’s Water Quality
Standards (OWRB 2008). However, in 2000, the COMCD, OWRB, and the three
municipalities receiving water from Lake Thunderbird (Norman, Midwest City, and Del
City) set goals for an upper limit of 20 μg/L of chlorophyll­a
for open water sites during
the growing season (OWRB 2001b). This will be an interim target for improvement in
the lake.
Lake Thunderbird’s designated beneficial uses include Aesthetics, Agriculture, Warm
Water Aquatic Community, Primary Body Contact Recreation, Public and Private Water
Supply, Fish Consumption, and Sensitive Water Supply. The tributaries to Lake
Thunderbird have these same designated uses, with the exception of Moore Creek,
which does not have the Sensitive Water Supply designation. Only the criteria for the
listed causes of impairment (from Table 3) are presented below, along with the criteria
Lake Thunderbird WBP June 2010
­27
­for
the Sensitive Water Supply (SWS) and Nutrient Limited Watershed (NLW)
designation.
To determine attainment of the Primary Body Contact Recreation use (for streams),
samples must be collected during the recreation season, from May 1­September
30,
and at least ten samples are required to make an attainment assessment.
To attain the PBCR use:
· Escherichia coli (E. coli)
a) No sample shall exceed 406 colonies/100 ml.
b) Monthly geometric mean must be less than 126 colonies/100 ml.
To attain Warm Water Aquatic Community use:
· Turbidity (only applicable during baseflow)
a) No more than 10% of samples will exceed 25 NTU (for lakes).
b) No more than 10% of samples will exceed 50 NTU (for streams)
· Dissolved oxygen (DO)
a) No more than 50% of the water column at any given sample site in a lake
or an arm of a lake will be below 2 mg/L due to other than naturally
occurring conditions (for lakes).
b) No more than 10% of samples will be below 5 mg/L, or 4 mg/L from June
16­October
15, based on at least 10 samples (for streams).
A minimum of ten samples is required to make an attainment determination for any
agriculture parameter. To attain the Agriculture use (for streams):
· Total dissolved solids (TDS)
a) Samples shall not exceed 700 mg/L. If any sample exceeds 700 mg/L,
then the yearly mean shall not exceed 265 mg/L, and no more than 10%
of the samples shall exceed 294 mg/L (values specific to waterbody
segment 520810).
Sensitive Water Supply designation:
The "sensitive water supply" (SWS) designation means that new point source
discharges of any pollutant and increased load of any pollutant from any point source
discharge shall be prohibited in these waterbodies or watersheds unless the discharger
“demonstrates to the satisfaction of the permitting authority that a new point source
discharge or increased load from an existing point source discharge will result in
maintaining or improving the water quality of both the direct receiving water and any
downstream waterbodies designated SWS.” In addition, a waterbody designated SWS
shall not have long­term
average concentrations of chlorophyll­a
at 0.5 meters below
the lake surface of greater than 10 mg/L.
Nutrient Limited Watershed designation:
A nutrient limited watershed is one in which a designated beneficial use is adversely
affected by excess nutrients as determined by Carlson’s Trophic State Index using
chlorophyll­a
of 62 or greater.
Lake Thunderbird WBP June 2010
­28
­All
of the above criteria stem from Oklahoma’s Water Quality Standards (OAC 785:45,
OWRB 2008). Attainment of these criteria will indicate full success of the WBP. The
procedures by which the data must be collected and analyzed to verify whether or not
these criteria have been met are identified in Oklahoma’s Use Support Assessment
Protocols (OAC 785:46, OWRB 2008). Progress toward achieving these criteria will be
gauged through monitoring by both the OWRB (in­lake
data) and the OCC (stream
data).
Any improvement in the parameters described above will be considered indicative of
success in the watershed. It is expected that complete attainment of the water quality
criteria will not occur for several years after implementation of BMPs, especially in the
lake itself, since there is a lag time between BMP implementation and observable water
quality changes, especially in large waterbodies. After release of the TMDL, more
specific interim criteria can be set.
For the initial LID project, the OCC will compare water quality from runoff events in the
control side of the neighborhood (built with conventional curbs and storm drains) to the
LID side of the neighborhood (built with rain gardens to filter runoff from the street and
lots). The effect of this single project in the watershed is expected to be small; however,
the results of this monitoring (details in a later section) will be used to guide future LID
projects in the watershed.
As future projects are implemented by the OCC or other entities, the WBP will be
updated, and expected load reductions will be calculated. Data from ambient
monitoring in the watershed will be assessed on a regular basis and compared with
modeling results to determine whether revisions are necessary.
IMPLEMENTATION SCHEDULE and INTERIM MILESTONES (elements f and g)
Education, implementation, and demonstration of BMPs should reduce the overall load
of nutrients, sediment, and bacteria entering the waterbodies of the Lake Thunderbird
watershed and ultimately reaching the lake. Implementation of best management
practices will focus on low impact development in urban areas as well as some riparian
reestablishment and stream bank protection. The effects of implementation programs in
the watershed on bacteria, nutrient, and sediment loading from the various sources will
be evaluated at the end of the project as well as every five years to determine the future
strategy to be followed. This Watershed Based Plan will be revised approximately
every two years to reflect new information and address short­comings
identified with
earlier plans.
The initial goal is that at least a fifty­eight
percent total phosphorus load reduction will be
achieved through multiple activities in the watershed. Until this load reduction can be
proven with water quality data, it will be demonstrated by modeling the expected load
reductions from implemented practices. Goals for improvement in dissolved oxygen
and turbidity will be added to the plan once these TMDLs have been completed. Table
Lake Thunderbird WBP June 2010
­29
­7
details the schedule of the goals and actions of the WBP and long­term
load
reductions, as well as some interim activities. The “ultimate total load reduction” goal is
based on the expected 2030 build­out
scenario as described in Vieux (2007).
Table 8 presents interim milestones planned for the current LID project (Trailwoods).
Figure 10 shows the timeline of the Trailwoods project, which will be implemented in two
phases, as denoted by the vertical dashed line in that figure. More specific timeframes
are given in the workplans and QAPPs related to this project.
There is ongoing long­term
monitoring to assess water quality in the lake. The OWRB
will continue to collect water quality data and source information, and the OCC will
install autosamplers to insure that load reductions in the watershed can be measured
throughout the project period. Trend analyses will be performed on the various data
sets (bacteria, turbidity, lake chlorophyll­a
concentrations, TSIs, and nutrient
concentrations and loading) and will be evaluated at three year intervals with the
revisions of the WBP to determine whether measurable changes have occurred in water
quality.
Table 7. Schedule and Load Reduction Goals Associated with Activities Planned.
Goal Action Parameter
to Address
Initial Load
Reduction
Ultimate
Total Load
Reduction
Year to
Begin
Year to
Evaluate
and Adjust
Year to
Complete
SWAT modeling and
targeting
Nutrients,
Sediment complete complete
TMDL development
Dissolved
oxygen,
Turbidity
2008 2011
Characterize
NPS
contributions and
evaluate nutrient
dynamics and
impacts in
watershed Treatment Wetlands
study
Nutrients,
Sediment
NA NA
2010 2013
Compile and review LID
ordinances in nearby
states
complete complete
Send city planners / staff
to LID training workshop 2010 annually
Implement LID tour for
city planners / staff 2011 annually
OCC Blue Thumb
Program ongoing annually ongoing
Education and
outreach
programs
Municipal Stormwater
Programs ongoing ongoing
Trailwoods
319 project 2008 2011 2014
Implement urban
BMPs City of Norman
Stormwater Master Plan
Programs
Nutrients,
Sediment,
Pathogens
58% overall
NPS
phosphorus
load
68% overall
NPS
phosphorus
load
ongoing ongoing
OCC – Trailwoods
project
Nutrients,
Sediment 2011 2014
Water quality
monitoring
programs
Municipal Stormwater
Monitoring
Nutrients,
Sediment,
Pathogens
NA NA
ongoing ongoing
Lake Thunderbird WBP June 2010
­30
­Goal
Action Parameter
to Address
Initial Load
Reduction
Ultimate
Total Load
Reduction
Year to
Begin
Year to
Evaluate
and Adjust
Year to
Complete
OWRB – Beneficial Use
Monitoring Program
Nutrients,
Sediment,
Pathogens
ongoing ongoing
OCC –
Blue Thumb Program
Nutrients,
Sediment,
Pathogens
ongoing ongoing
ODEQ –
TMDL monitoring,
NPDES permitting
Nutrients,
Sediment,
Pathogens
ongoing ongoing
Table 8. Interim milestones for current OCC 319 project (Trailwoods Demonstration Site).
Task Description Time Frame
Investigation of site conditions, regulatory constraints, and
opportunities pertaining to LID practice implementation at the site November 2009
Determine similar sub­basins
within project area and conduct
preliminary planning of neighborhood design and LID BMP
implementation
February 2010
Complete necessary planning and draft conceptual design February 2010
Finalize design and complete construction drawings and BMP
specs May 2010
Implement construction of demonstration neighborhood Projected completion
June 2011
Develop model to assess life cycle costs of selected BMPs
compared to conventional design December 2011
Phase I
BMP Implementation:
Design and Construct
Demonstration
Neighborhood
Update life cycle cost models with actual benefit data realized at
the conclusion of the project period / Final analysis report May 2014
Hold Blue Thumb Training in watershed biannually
Organize and facilitate LID workshop for OK civic officials December 2010
Informational report September 2011
Model LID code September 2013
Organize and facilitate a LID training program for civic officials May 2014
Watershed
Education
Track behavioral change Throughout project
Water Quality Monitoring in Support of TMDL Development QAPP April 2008
Install autosamplers and begin monitoring May 2008
Trailwoods Demonstration Site Monitoring QAPP December 2010
Install autosamplers and begin Trailwoods demonstration site
monitoring January 2011
Update Thunderbird WBP to include ODEQ TMDL modeling results
and recommendations August 2011
Perform analysis of monitoring data – One year post­construction
completion December 2011
Perform analysis of monitoring data – Two years post­construction
completion December 2012
Water Quality
Monitoring /
Assessment
Perform final analysis of monitoring data May 2014
Lake Thunderbird WBP June 2010
­31
­Figure
10. Timeline for Trailwoods LID Demonstration Project.
MONITORING PLAN (element i)
Every Watershed Based Plan requires a monitoring plan to gauge the overall success of
restoration and remediation efforts. The goal of the monitoring plan for this WBP will be
to develop a long­range
monitoring program that will oversee the restoration of the
beneficial use support in the watershed and preserve its natural resources for future
generations.
The monitoring plan for this WBP provides for development of individual monitoring
plans and associated quality assurance plans and Standard Operating Procedures for
each underlying project or effort working toward the ultimate goal of restoration of
beneficial use support. These monitoring efforts are based on Oklahoma’s Water
Quality Standards and Use Support Assessment Protocols which define the process by
which beneficial use support can be determined. Technical assistance in developing
these plans can come from various sources, including the Oklahoma State Agency peer
review process.
Methodologies developed for use in this WBP will be selected to provide: 1) a
quantifiable measure of changes in parameters of concern, 2) success measures that
can be easily understood by cooperators and stakeholders with a variety of technical
backgrounds, and 3) consistent, compatible information throughout the watershed.
Monitoring will focus on the primary causes of impairment, as listed in the 303(d) list,
but will also consider related causes that may exacerbate the impacts of the primary
causes or may ultimately reach impairment levels without improved management. As
the WBP evolves and expands to be more inclusive of all the parameters of concern, it
is anticipated that this list will expand and contract. At this time, the following
parameters will continue to be monitored in the Lake Thunderbird watershed:
· Water quality: nutrients, sediments, suspended solids, fecal bacteria, dissolved
oxygen, temperature, pH, conductivity, alkalinity, hardness, turbidity, chlorophyll­a,
BOD5
Lake Thunderbird WBP June 2010
­32
­
· Parameters for watershed model (TMDL) development: total organic carbon (TOC)
and dissolved organic carbon (DOC)
· Hydrologic budget: in­stream
flows, infiltration rates, aquifer recovery, groundwater
levels
· Landuse/land cover: acreage in different landuses, quality and type of land cover,
timing and other variables of associated management practices
· Riparian condition: extent and quality of riparian zones in the watershed to include
quality and type of vegetation, degree of impact or stability, condition of
streambanks, and primary source of threat or impact
· Aquatic biological communities: assessment of the condition of fish and benthic
macroinvertebrate communities related to reference streams and biocriteria
· BMP and other implementation efforts: type, extent, and specific location of
practices to include an estimate of the potential load reduction due to
implementation
· Behavioral change: participation in Watershed Based Plan­related
activities and
behavioral changes of affected communities
With each WBP­related
program, as well as for the WBP as a whole, baseline
conditions will be established and monitored prior to implementation. A monitoring
schedule and Quality Assurance Project Plan (QAPP) will be developed based on the
type of project and timing of its implementation. Monitoring results will be reported to
the appropriate entities as defined in the QAPPs.
Baseline Data
Water Quality
The baseline data to evaluate progress in the Lake Thunderbird Watershed has been
established by several monitoring efforts in the watershed. Until a TMDL is drafted and
officially approved, water quality in this WBP will be guided by the following:
· Oklahoma Integrated Report – Clean Water Act Section 303(d) List of Waters
needing a TMDL, 2008. Lake Thunderbird, Hog Creek, West Hog Creek, Elm
Creek, East Elm Creek, and Moore Creek are of concern because they are on
the 2008 303(d) list as impaired due to one or more of the following: chlorophyll­a,
turbidity, pathogens, low dissolved oxygen, or TDS.
· OCC monitoring – Elm Creek was monitored monthly as part of the “East of I­35
Project” from 2/1999 – 3/2001. In addition, West Elm Creek has been monitored
as part of the Blue Thumb project from 5/1998 – 6/2006.
· OWRB BUMP monitoring – Lake Thunderbird has been monitored quarterly for
one year every other year since 1998. This data was the basis for the SWAT
modeling performed by Vieux (2007).
· City of Oklahoma City Stormwater Division monitoring – Data was collected
for Hog Creek, West Hog Creek, and East Elm Creek as part of a watershed
characterization project in 2004 and 2005.
Lake Thunderbird WBP June 2010
­33
­Hydrologic
Budget
· USGS – There is one USGS stream gauge near the watershed, just below Lake
Thunderbird on the Little River.
Landuse/Land Cover
· NRCS and OCC – Color digital orthophotos (2003).
· OCC and contractors – Modeling the Lake Thunderbird Watershed Using
SWAT 2000 using geospatial data provided by the Association of Central
Oklahoma Governments (ACOG) Water Services Division, current as of 2000
(Vieux 2007). ACOG assembled and analyzed future landuse plans projected to
the year 2030 based on information provided by the municipalities within the
watershed.
Riparian Condition
· NRCS and OCC – Color digital orthophotos (2003).
· OCC and contractors – Modeling the Lake Thunderbird Watershed Using
SWAT 2000 (Vieux 2007).
Best Management Practices and Other Implementation Efforts (Coverages)
· NRCS/FSA – Records of specific practices installed and associated
costs of programs such as EQIP
· OCC and contractors – Estimates of load reductions related to installation of
specific practices through computer modeling
· ODEQ – Permit upgrades for NPDES permitees in the watershed
· OWRB – Infrastructure upgrades supported through the State Revolving Fund
Loan program
Data Collection Responsibilities
Responsibility for the collection of additional data of the types described above will
reside with project managers of the individual projects as detailed in individual work
plans. These project managers will be responsible for ensuring that the data is
submitted to the ODEQ for inclusion in the Oklahoma State Water Quality Database,
which will ultimately be uploaded to the National STORET database. Data reporting
under individual workplans will also be the responsibility of the project managers.
Monitoring results for all projects will be available and accessible to the public through
the posting of final reports on agency websites.
In addition to those monitors to be identified in the workplans of the individual projects
under this WBP, the following groups will be involved in monitoring activities:
· Oklahoma Water Resources Board (OWRB): Beneficial Use Monitoring Program
and Oklahoma Water Watch Monitoring Program
· Oklahoma Conservation Commission (OCC): Priority Watershed Project
Monitoring, Rotating Basin Monitoring, and Blue Thumb Project Monitoring; data
Lake Thunderbird WBP June 2010
­34
­collected
will be in support of both the 319 implementation project and the
ODEQ’s TMDL/WBP development for Lake Thunderbird
· U.S. Geological Survey (USGS): surface and groundwater quality and quantity
monitoring and special studies
Monitoring Details
Stream Monitoring
The OCC installed five autosamplers in the Thunderbird Watershed at the locations
given in Table 9 and Figure 11. These autosamplers collected continuous, flow­weighted
composited samples from April 2008 through April 2009. Grab samples were
collected at these locations as well, as detailed in Table 10. This data is being used by
the ODEQ to develop the TMDL for the lake and to establish pre­implementation
loads
in the major tributaries to the lake.
Table 9. Autosampler locations in the Lake Thunderbird Watershed.
Site Name WBID Legal Latitude Longitude
Little River @ 17th OK520810­00­0080W
NW¼ SE¼ SE¼
Section 22­10N­3W
35.3235 ­97.4963
West Elm Creek @ 134th OK520810­00­0140P
SE¼ SW¼ SW¼
Section 14­10N­2W
35.334 ­97.3854
Little River @ 60th OK520810­00­0080H
SE¼ SE¼ SE¼
Section 1­9N­2W
35.2778 ­97.3536
Rock Creek @ 72nd OK520810­00­0090C
NW¼ NW¼ NW¼
Section 17­9N­1W
35.261 ­97.3354
Hog Creek @ 119th OK520810­00­0030G
SE¼ SE¼ SW¼
Section 12­10N­1W
35.3483 ­97.2585
Table 10. OCC analytical parameters and sampling frequency.
Parameter Collection Frequency
Dissolved Oxygen, Conductivity, pH, Temperature, Alkalinity,
Turbidity, Instantaneous Discharge
weekly (in­situ)
;
high flow events
Total Organic Carbon, Ortho­phosphorus
(dissolved),
Nitrate/Nitrite (dissolved), Ammonia (dissolved), TSS
weekly grab samples;
high flow events
Total Phosphorus, TKN
weekly autosampler samples;
high flow events;
grab samples when
autosampler failure events
Dissolved Organic Carbon grab samples every 3 weeks
Chloride, Sulfate, Hardness, TDS monthly grab samples;
high flow events
E. coli, Enterococcus
weekly grab samples
from April 1 – October 30;
high flow events
Precipitation, Accumulated Flow weekly download;
high flow event download
Lake Thunderbird WBP June 2010
­35
­#
#
#
#
#
Cleveland Co.
Oklahoma Co.
Little River
West Elm Creek
Hog Creek
Rock Creek
Lake Thunderbird
Lake StanleyD raper
Lake Thunderbird Watershed
# Autosamplers
OSAG E
TE XAS
KA Y
ELL IS
BE AVE R
CADD O
CMI AR RO N
LE FL O RE
WO OD S
MCC URT AI N
GR AD Y
KOI WA
ATOK A
GRAN T
CR EEK
BRY AN
MA J OR
DE WEY BLANI E
HAR PE R
CUS TE R
PTI T S BUR G
CR AI G
IL NC OLN
NO BLE
WA S HIT A
LO GA N
GARV NI
GARF I ELD
TIL LM AN
PAY NE
PUSH M AT AH A
ALFA LFA
CA RTE R
LO VE
MAY ES
WO ODWAR D
COAL
HUGH ES
ADAIR
COM ANC H E
BE CKH AM
TUL SA
GREE R
CAN AD IA N
JA CKS O N
LA TIM ER
ROG ER MIL LS
STEP HE NS
RO G ER S
CH OC TAW
COT T O N
KNI G F IS HER
MU SK OGE E
DE LAWARE
HAS KE L
CH ER OKEE
PA WNEE
MC I NTO S H
JE FF ERS O N
NOWAT A
MCC L ANI
PON TO T OC
OKLA H OM A
SE QU OYAH
SE MI NO LE
OK M ULGEE
HAR M ON
JO HNS TON
OK FUS KEE
OT T AWA
WA G ON ER
MU R RA Y
POTTA WAT O MI E
CLEV ELAN D
MARS HAL L
WAS HNI GTO N
S
N
W E
Figure 11. Location of autosamplers in the Lake Thunderbird watershed.
OCC will rely on OWRB lake monitoring data to assess whether or not practices have
resulted in improved lake water quality throughout the project. Biological and habitat
monitoring will not be completed as part of this project in order to minimize project
expenses and since the project size is unlikely to significantly impact habitat availability
in the watershed. In addition, specific single landuse areas will be sampled during
runoff events for better model calibration.
In the Trailwoods project, storm water quality and quantity differences between the two
streets (conventional versus LID) will be assessed using continuous flow monitoring
systems (e.g., weirs or flumes with data­logging
pressure transducers or bubblers),
automatic flow­activated
composite samplers, and tipping­bucket
rain gauges at the
base of each street. Composite storm water samples will be analyzed for physical
parameters (e.g., pH, dissolved oxygen, temperature, specific conductance, etc.), total
suspended solids, biochemical oxygen demand, total and dissolved reactive
phosphorus, nitrate­nitrogen,
ammonia­nitrogen,
copper, lead, zinc, oil and grease, and
selected common herbicides and pesticides. Suspended sediment concentration may
be substituted for TSS if it is cost comparable. Storm hydrographs will be developed
and evaluation will include calculation of runoff volumes, peak discharge, runoff depths,
lag times, concentration changes, and area­adjusted
mass loadings and exports. It is
hypothesized that significant differences will be realized between the two watersheds.
Monitoring for this project will not begin until construction is complete, tentatively
January 2011. Additional water quality monitoring will be necessary to document
success of other LID implementation areas as they are implemented. This monitoring
Lake Thunderbird WBP June 2010
­36
­will
be funded under future project grants, and details will be provided in updates to the
WBP.
Lake Monitoring
The OWRB will continue to monitor Lake Thunderbird as part of the BUMP. This
involves quarterly sampling every other year in which the following parameters are
monitored: temperature, pH, dissolved oxygen, salinity, dissolved oxygen % saturation,
oxidation­reduction
potential (redox), specific conductance, total dissolved solids (TDS),
turbidity, Secchi disk depths, nitrate nitrogen, nitrite nitrogen, ammonia nitrogen,
kjeldahl nitrogen, orthophosphorus, total phosphorus, true color, chloride, sulfate, total
alkalinity, chlorophyll­a,
and pheophytin. Vertical water quality profiles are recorded at
one meter intervals from the lake surface to the lake bottom for at least three sites per
reservoir: in the central pool area near the dam (lacustrine zone), in the upper portion
of the lake and in the major arms of the water body (riverine zone), and in the area
between the lacustrine zone and the riverine zone (transitional zone). In addition, the
OWRB is contracted to monitor the lake annually from April through October to provide
information to the COMCD.
Landuse/Landcover
Comparisons of landuse/landcover will be made throughout the project as new data
becomes available. The SWAT model used geospatial landuse data provided by the
Association of Central Oklahoma Governments (ACOG) Water Services Division,
current as of 2000, and this data will be requested periodically as new coverages
become available. In addition, census data will be updated in the WBP as it is released
so that the expected urbanization in the watershed is accurately represented.
Best Management Practice Implementation
Summaries of BMP implementation will be included in final reports at the conclusion of
each project in the watershed. Maps showing implementation in relation to hotspot
areas (based on SWAT modeling) in the watershed will be included in the assessment
of BMP implementation. This information will be inserted into the WBP as it becomes
available.
Benefits of the Monitoring Plan
Implementation of this monitoring plan will enable Lake Thunderbird watershed partners
to meet the goals of the WBP, which is ultimately to restore beneficial use support to
waters of the watershed. Implementation of the monitoring plan will help further define
areas of the watershed where restoration activities should be focused to realize the
optimum benefit for the investment as well as evaluate the impacts (realized and
potential) of implementation efforts. Collection of the data described under this
monitoring plan will help define the relative contributions from various sources in the
watershed and the processes contributing to water quality degradation in the watershed.
Finally, continued collection of this data and evolution of the monitoring plan for the
watershed will allow the program to adapt to meet the changing needs of watershed
protection in the Lake Thunderbird Watershed.
Lake Thunderbird WBP June 2010
­37
­TECHNICAL
and FINANCIAL ASSISTANCE NEEDED (element d)
Funding needs are difficult to anticipate and will likely change over time. The estimated
costs associated with the current projects in the watershed are highly conservative and
will change as the TMDL is finalized and further information becomes available.
Potential project funding in this watershed includes money from the EPA 319 program,
state programs (OCC, OWRB, ODEQ), municipalities (Norman, Moore, Oklahoma City),
and private entities (COMCD). Additional funds beyond those available in the OCC
2007­2008
319 grants will be necessary to complete the proposed implementation, so
the project will be executed in a phased approach. Initial estimates of the funds to carry
out phase 1 of the Trailwoods LID project are shown in Table 11, below, along with
activities of other agencies in the watershed.
Technical assistance will be in the form of peer review of proposed projects from the
NPS working group and data­sharing
from the entities listed in Table 11. OCC is
working with the cities in the watershed to educate, monitor, model, and implement
BMPs. Although EPA funds have been and will likely continue to be allocated toward
this effort, cities are devoting considerable funds towards activities in the watershed as
well. OCC will work with cities to provide a better accounting of their anticipated needs
for funding, as well as their ongoing investments in water programs which may be used
for in­kind
match of federal funds, in future iterations of the WBP.
Table 11. Funding for specific projects/efforts.
Task Program Federal State Total Agency Status
Trailwoods 319 LID
Demo Project (phase 1) $297,578 $214,656 $512,234 OCC Ongoing
Lake Thunderbird
Aeration Project $692,773 OWRB Ongoing
Erosion Control /
Shoreline Stabilization
Demo Project
$6,500 OWRB Completed
BMP
Implementation
Stormwater Master
Plan Projects $83,000,000 City of
Norman Planned
319 Project /
Blue Thumb $Education and 182,724 OCC Planned
Outreach Stormwater Master
Plan Projects ? City of
Norman Planned
Autosampler monitoring
in support of TMDL $10,249 OCC /
ODEQ Completed
Trailwoods 319 LID
Demo Project $44,940 OCC Planned
Monitoring
BUMP & COMCD
(Lake Thunderbird only)
$90,000
annually
OWRB /
COMCD Ongoing
Computer
Modeling
SWAT project to target
NPS pollution $89,774 $89,774 OCC Completed
Lake Thunderbird WBP June 2010
­38
­HSPF
watershed model
for TMDL $78,000 ODEQ Ongoing
EFDC lake model for
TMDL $164,774 ODEQ Ongoing
REFERENCES
Cole, Carol. 2007. Council to consider storm water plan contract. Norman Transcript,
July 9, 2007.
COMCD. 2006. Rock Creek Watershed Analysis and Water Quality Evaluation.
Prepared for the Central Oklahoma Master Conservancy District by Vieux and
Associates, Inc.
ODEQ. 2008. Integrated Report. Oklahoma Department of Environmental Quality.
McNab, W.H. and P.E. Avers. 1994. Ecological Subregions of the United States. USDA,
Forest Service.
OWRB. 2001a. Shoreline Erosion Control Plan, Lake Thunderbird, Cleveland County,
Oklahoma. AllEnVironment Consulting, for Oklahoma Water Resources Board.
OWRB. 2001b. Evaluation of Lake Thunderbird Water Quality Management Practices
for the Central Oklahoma Master Conservancy District. Oklahoma Water
Resources Board.
OWRB. 2002. Lake Thunderbird Capacity and Water Quality 2001, Final Report for the
Central Oklahoma Master Conservancy District. Oklahoma Water Resources
Board.
OWRB. 2003. Lake Thunderbird Algae and Water Quality, Final Report for the Central
Oklahoma Master Conservancy District. Oklahoma Water Resources Board.
OWRB. 2008. Oklahoma Water Quality Standards, Oklahoma Administrative Code,
Chapter 45. Oklahoma Water Resources Board.
OWRB. 2008. Implementation of Oklahoma’s Water Quality Standards, Oklahoma
Administrative Code, Chapter 46. Oklahoma Water Resources Board.
OWRB. 2006. Agency Rule Report, Amendments to Title 785. Oklahoma Water
Quality Standards, Oklahoma Administrative Code, Chapter 45. Oklahoma
Water Resources Board.
Vieux and Associates, Inc. 2007. Lake Thunderbird Watershed Analysis and Water
Quality Evaluation. Report for Oklahoma Conservation Commission.

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WATERSHED BASED PLAN
FOR THE
LAKE THUNDERBIRD WATERSHED
Photo courtesy of OTRD
Prepared By:
Oklahoma Conservation Commission
Water Quality Division
2800 N. Lincoln Blvd., Suite 160
Oklahoma City, OK 73105
(405) 522­4500
Lake Thunderbird WBP June 2010
­2
­Table
of Contents
LIST OF TABLES 3
LIST OF FIGURES 3
PREFACE 4
INTRODUCTION 6
CAUSES and SOURCES 7
LOAD REDUCTIONS 17
NPS MANAGEMENT MEASURES 18
PUBLIC OUTREACH 24
CRITERIA 26
IMPLEMENTATION SCHEDULE and INTERIM MILESTONES 28
MONITORING PLAN 31
TECHNICAL and FINANCIAL ASSISTANCE NEEDED 37
REFERENCES 38
Lake Thunderbird WBP June 2010
­3
­LIST
OF TABLES
Table 1. Population growth in Cleveland and Oklahoma Counties 10
Table 2. Landuse in the Lake Thunderbird watershed 10
Table 3. Waterbodies in the Lake Thunderbird watershed 12
Table 4. Livestock in Oklahoma and Cleveland Counties 16
Table 5. Possible management practices for urban areas 20
Table 6. Impact of targeted BMPs on phosphorus and chlorophyll­a
23
Table 7. Schedule and load reduction goals 29
Table 8. Interim milestones for Trailwoods project 30
Table 9. Autosampler locations in the Lake Thunderbird Watershed 34
Table 10. OCC analytical parameters and sampling frequency 34
Table 11. Funding for specific projects/efforts 37
LIST OF FIGURES
Figure 1. Lake Thunderbird watershed 7
Figure 2. Municipalities in the Lake Thunderbird watershed 9
Figure 3. Landuse in the Lake Thunderbird watershed 11
Figure 4. Location of highest total phosphorus yields 13
Figure 5. Location of highest sediment yields 14
Figure 6. Percent change in percent impervious area from baseline to build­out
14
Figure 7. Location of permitted total retention lagoons and oil/gas wells …..15
Figure 8. Street design of Trailwoods project and location in watershed 18
Figure 9. Potential wetland development sites 22
Figure 10. Timeline for Trailwoods LID Demonstration Project 31
Figure 11. Location of autosamplers in the Lake Thunderbird watershed 35
Lake Thunderbird WBP June 2010
­4
­PREFACE
Lake Thunderbird, located in central Oklahoma, is a popular recreational lake as well as
a water supply reservoir for the cities of Norman, Del City, and Midwest City, which
have a combined population of approximately 178,000. Significant taste and odor
problems, linked to eutrophication in the lake, have led to complaints from water users.
According to the Oklahoma Department of Environmental Quality (ODEQ) 2008
Integrated Report, Lake Thunderbird is not supporting its Fish and Wildlife Propagation
(Warm Water Aquatic Community) designated use due to turbidity and low dissolved
oxygen (DO), its Aesthetics use due to color, or its Public Water Supply use due to
chlorophyll­a.
The chlorophyll­a
concentration is approximately three times the water
quality standard required for a sensitive water supply. Other impaired waterbodies in
the watershed include 1) Hog Creek, impaired by turbidity and low DO, 2) West Branch
of Hog Creek, impaired by low DO, 3) Moore Creek, impaired by total dissolved solids
(TDS), 4) Elm Creek, impaired by E. coli, turbidity, and TDS, and 5) East Elm Creek,
impaired by low DO.
Excessive nutrient loading in the watershed, primarily from urban development, has
caused the observed eutrophication in the lake. The Central Oklahoma Master
Conservancy District (COMCD), in cooperation with the Oklahoma Water Resources
Board (OWRB), has been monitoring chlorophyll­a
and nutrient concentrations in the
lake since 2000 and has implemented several management alternatives that have
improved the lake’s algae and chlorophyll problems. However, further action is
necessary to achieve full attainment of designated beneficial uses in the watershed.
The Lake Thunderbird watershed covers 256 square miles (163,840 acres) in
Oklahoma and Cleveland Counties, with the major tributary being the Little River. The
watershed is approximately 60 percent agricultural (mostly pasture) and 40 percent
residential development. Significant, consistent population growth has occurred over
the past 30 years and is expected to continue in the area, with a great deal of pasture
being converted to urban areas. Without a proactive plan to address the potential
impact of this urban expansion, water quality in the area is expected to continue to
decline rapidly.
Based on SWAT model results by Vieux (2007), it is estimated that approximately
18,000 kg of phosphorus enters Lake Thunderbird each year. Nonpoint source (NPS)
pollution associated primarily with increased impervious surfaces due to urban growth
appears to be the primary source of the water quality problems in the Lake Thunderbird
watershed. Modeling of the watershed has resulted in a recommendation of a 58%
percent reduction (about 10,000 kg/yr) of total phosphorus to Lake Thunderbird in order
to produce acceptable water quality conditions (chlorophyll­a
concentration of 10 mg/L or
less) (OWRB 2006). A TMDL is currently being developed by the ODEQ for the lake to
address sediment and dissolved oxygen impairments. Load reduction estimates
resulting from this effort will be added to the watershed plan when the TMDL is
released.
Lake Thunderbird WBP June 2010
­5
­It
is projected that various low impact development (LID) practices could dramatically
improve the nutrient and sediment loading in the watershed in a relatively short time
frame. The Lake Thunderbird Watershed Based Plan (WBP) refers to the initial
implementation of actions focused on LID, which are necessary to restore beneficial use
support to Lake Thunderbird and its tributaries.
Lake Thunderbird WBP June 2010
­6
­INTRODUCTION
The Nonpoint Source Program and Grants Guidelines for States and Territories for FY
2004 and Beyond requires a Watershed Based Plan (WBP) to be completed prior to any
implementation efforts using incremental funds. The guidance describes nine key
components to be addressed in a watershed­based
plan, much of which builds from the
strategies outlined in the Watershed Restoration Action Strategy (WRAS). These
components include: 1) identification of causes and sources that will need to be
controlled to achieve load reductions, 2) estimate of load reductions expected from the
management measures described, 3) a description of the management measures that
will need to be implemented to achieve load reductions, 4) an estimate of the amounts
of technical and financial assistance needed, associated costs, and/or the sources or
authorities who will bear responsibility, 5) an information/education component that will
be used to enhance public understanding of the project and encourage early
participation in the overall program, 6) a schedule for implementing the NPS
management measures identified in this plan that is reasonably expeditious, 7) a
description of interim, measurable milestones for determining whether control actions
are being implemented, 8) a set of criteria that can be used to determine whether
loading reductions are being achieved over time and substantial progress is being made
or whether the Watershed Plan or Total Maximum Daily Load (TMDL) needs to be
revised, and 9) a monitoring component to evaluate the effectiveness of the
implementation efforts over time.
In order for the WBP to become an integral part of the entire watershed restoration
program, it must be amenable to revision and update. The Lake Thunderbird WBP has
been developed as a dynamic document that will be revised to incorporate the latest
information, address new strategies, and define new partnerships between watershed
stakeholders. It is anticipated that at least biannual revisions may be necessary and
that the responsibility for such revisions will rest primarily with the Oklahoma
Conservation Commission (OCC), with support from the Oklahoma Department of
Environmental Quality (ODEQ), Office of the Secretary of the Environment (OSE) and
the NPS Working Group. It is understood that the water quality goals and the technical
approach set forth in this WBP may not be comprehensive, so they may be expanded in
the future, especially as ODEQ’s work with the TMDL/WMP is completed. Federal and
state funding allocations for future water quality projects designed to address the Lake
Thunderbird Watershed problems should not be based solely upon their inclusion in this
WBP; rather, the WBP should be considered a focal point for initial planning and
strategy development.
Lake Thunderbird WBP June 2010
­7
­CAUSES
and SOURCES (element a)
Watershed Characterization
The Lake Thunderbird watershed (HUC 111090203010) covers a 163,840 acre area in
Cleveland and Oklahoma Counties. The principal tributary to Lake Thunderbird is the
Little River, which was impounded by the Bureau of Reclamation to form the lake in
1965. Other tributaries are shown in Figure 1. Designated uses of the dam and the
impounded water are flood control, municipal water supply, recreation, and fish and
wildlife propagation. Designated uses of streams in the watershed include aesthetics,
agriculture, warm water aquatic community (WWAC), industrial and municipal process
and cooling water (I & M), primary body contact recreation (PBCR), public and private
water supply (PPWS), fish consumption, and sensitive water supply (SWS).
Cleveland Co.
Oklahoma Co.
Hog Cr.
Kitchen Cr.
West Elm Cr
Elm Cr.
Little Riv er
Nort h Fork Little
Moore Cr.
Rock Cr.
Dav e Blue Cr.
Clear Cr.
Jim Blue Cr.
West Hog C
L. Stanley Draper
Lake Thunderbird
0 5 10 15 Miles
OSAG E
TEXAS
KAY
ELLIS
BEAV ER
CADD O
CMI AR RO N
LE FLO RE
WO ODS
MCC URTAIN
GRAD Y
KOI WA
ATOKA
GRAN T
CREEK
BRYAN
MAJ OR
DEW EY
BLANI E
HARPE R
CUST E R
PTI T S BURG
CRAIG
IL NC OLN
NOBLE
WA S HTI A
LO GAN
GARV IN
GARFI ELD
TIL LM AN
PAY NE
PUSHM AT AH A
ALFAL FA
CARTE R
LO VE
MAYES
WO ODW AR D
COAL
HUGH ES
AD AI R
COM ANCH E
BECKH AM
TUL SA
GRE E R
CA NAD IA N
JA CKSO N
LA TIM ER
ROG ER MIL LS
STEPHE NS
ROG ERS
CHOC TA W
COTT O N
KNI G FIS HER
MUSK OGE E
DELAW ARE
HASKE L
CHER OKEE
PAW NEE
MCI NTOS H
JE FF ERSO N
NO W ATA
MCC LANI
PONTO T OC
OKLAH OMA
SEQU OYAH
SEMI NOLE
OKM ULGEE
HARM ON
JO HNS TON
OKFUS KEE
OTT AW A
WA G ON ER
MUR RAY
POTT AW ATO MIE
CLEVEL AN D
MARS HAL L
W AS HNI GTO N
Figure 1. Lake Thunderbird watershed.
As a municipal water supply, Lake Thunderbird furnishes raw water for Del City,
Midwest City, and the City of Norman under the authority of the Central Oklahoma
Master Conservancy District (COMCD).
Lake Thunderbird WBP June 2010
­8
­The
morphologic features of Lake Thunderbird are (OWRB 2002):
Area 5,439 acres
Volume 105,838 acre­feet
Shoreline 96 km
Mean Depth 4.7 m (15.4 ft)
Maximum Depth 17.7 m (58 ft)
Water Supply Yield 21,700 acre­feet/
yr (19.4 mgd)
Mean Monthly Discharge/Outflow 74.5 cfs
All of these values represent a reduction since impoundment in 1966 due to
sedimentation. The overall sedimentation rate was estimated as 393 acre­feet
per year
with a total loss of 13,762 acre­feet,
about 12% higher than originally planned. Most of
the sediment accumulation has occurred in the upper portion of the conservation pool.
The decrease of surface area is mostly due to inflow of large­grained
solids from
tributaries (OWRB 2002).
Although the Lake Thunderbird watershed contains Lake Stanley Draper and its
watershed (Figure 1), this area was removed from modeling analyses since discharges
are not allowed over the spillway. This means that seepage under the dam is the only
way that water from the Lake Stanley Draper watershed could enter Lake Thunderbird.
Since any seepage is minimal, Lake Stanley Draper is not considered a source of
nutrient loading to Lake Thunderbird and will not be shown in any of the other figures.
The Lake Thunderbird watershed is located in the Central Great Plains and Cross
Timbers ecoregions (Woods et al. 2005). The Central Great Plains ecoregion is a
transition area between mixed grass prairie in the west, now primarily a winter wheat
growing region, and forested low mountains in eastern Oklahoma. “Gently sloping
narrow ridgetops are separated by steep slopes bordering drainage ways. Some
stream valleys with nearly level flood plains and large stream terraces exist. Dissected
plains with broad rolling ridgetops and moderately steep valley sides occur. Valleys are
usually narrow with broad flood plains and terraces and hilly dissected plains. There
are rivers with wide flood plains and terraces and small streams with narrow
bottomlands. Rolling plains have a deep mantle of windblown sand and sandy outwash.
Elevation ranges from 1,310 to 2,950 ft (400 to 900 m). Soils include Mollisols and
Alfisols” (McNab and Avers 1994). Predominant vegetation includes bluestem­grama
prairie, sandsage­bluestem
prairie, northern flood plain forests, and buffalo grass.
Precipitation ranges from 20 to 35 inches (500 to 900 mm), and temperature averages
50 to 61 degrees F (10 to 16 degrees C). “Groundwater is abundant in areas
associated with sand and gravel deposits; however, it is scarce and may be mineralized
in areas where shale, sandstone, clay, and limestone are near the surface” (McNab and
Avers 1994).
The Cross Timbers ecoregion “is a region of rolling hills and narrow valleys. The terrain
generally is more complex than other parts of central Oklahoma. Elevation ranges from
330 to 1,300 ft (100 to 400 m). Soils in the Cross Timbers ecoregion are mainly Ustalfs.
Lake Thunderbird WBP June 2010
­9
­Soils
are deep, well drained, and fine to moderate textured; moisture is limited for use
by vegetation during part of the growing season” (McNab and Avers 1994). Oak­hickory
and oak­hickory­pine
forest and extensive areas of tall grassland with a tree layer
comprise the ecoregion. Forest cover consists of post, live, and blackjack oaks, and
pignut and mockernut hickories. Grasses consist of big and little bluestems, Indian
grass, and sunflower. Precipitation averages 35 to 40 inches (900 to 1,050 mm), and
temperature averages 55 to 63 degrees F (13 to 17 degrees C) (McNab and Avers
1994).
Human Population:
The population in Cleveland County, where the majority of the Lake Thunderbird
watershed is located, is 224,898 (2005 Census). The city of Norman, which comprises
about half of the watershed area (Figure 2), is the largest city in the county, with
approximately 102,000 residents (86% urban). The city of Moore makes up about 8
percent of the watershed area and has a population of nearly 45,000. There has been a
steady increase in Cleveland County’s population since 1960, especially in urban areas
(Table 1).
Figure 2. Municipalities in the Lake Thunderbird watershed (Vieux 2007).
About 38% of the Lake Thunderbird watershed area is located within the Oklahoma City
municipal boundary. In Oklahoma County, the population is 691,266, with 523,303
Lake Thunderbird WBP June 2010
­10
­located
within Oklahoma City (2005 Census). The population in Oklahoma County has
also shown consistent growth (Table 1).
Table 1. Population growth in Cleveland and Oklahoma Counties.
County Parameter 1960 1970 1980 1990 2000
Total population 47,600 81,839 133,173 Cleveland 174,253 208,016
Percent change 71.93% 62.73% 30.85% 19.38%
Oklahoma Total population 439,506 527,717 568,933 599,611 660,448
Percent change 20.07% 7.81% 5.39% 10.15%
Landuse:
As shown in Table 2 and Figure 3, approximately 60 percent of the watershed is
agricultural, with pasture comprising the majority of the agriculture land. Most of the
remainder of the watershed is developed, primarily residential.
Table 2. Landuse in the Lake Thunderbird watershed.
Landuse Percent of Watershed Area
Residential Medium Density 26.00
Residential High Density 0.07
Agricultural – Pasture 53.84
Agricultural­Generic
(parks and open spaces) 7.62
Commercial 0.68
Industrial 1.39
Transportation 4.18
Institutional 1.17
Open Water 5.05
Lake Thunderbird WBP June 2010
­11
­Figure
3. Landuse in the Lake Thunderbird watershed (Vieux 2007).
Causes
The designated beneficial uses for Lake Thunderbird and its tributaries include
Aesthetics, Agriculture, Warm Water Aquatic Community, Primary Body Contact
Recreation, Public and Private Water Supply, Fish Consumption, Industrial and
Municipal Process and Cooling Water, and, for the lake itself, Sensitive Water Supply.
The impaired designated uses and the causes of non­attainment
of designated uses are
shown in Table 3. Lake Thunderbird is listed in Oklahoma’s Integrated Report as a
Category 5 waterbody with impairment of the fish and wildlife propagation beneficial use
due to excess turbidity and low dissolved oxygen as well as non­attainment
of the public
and private water supply beneficial use due to high chlorophyll­a.
The three streams in
the Thunderbird watershed with enough monitoring data to assess designated beneficial
uses (Hog Creek, Elm Creek, and Moore Creek) are listed as impaired for one or more
assigned uses. It is likely that other streams in the watershed are impaired as well, but
not enough data has existed to make an assessment; for the next reporting cycle, the
OCC will have enough data to assess five additional streams in the watershed (Table
9). The WBP will be updated with the results of that assessment when it is performed.
Lake Thunderbird WBP June 2010
­12
­Table
3. Waterbodies in the Lake Thunderbird watershed (ODEQ 2008).
Waterbody ID Site Name Impaired Designated Uses Causes of Impairment
OK520810000020_00 Thunderbird Lake Warm Water Aquatic Community
Public and Private Water Supply
turbidity, low DO
chlorophyll­a
OK520810000030_00 Hog Creek Warm Water Aquatic Community turbidity, low DO
OK520810000040_00 West Hog Creek Warm Water Aquatic Community low DO
OK520810000050_00 Clear Creek *
OK520810000060_00 Dave Blue Creek *
OK520810000070_00 Jim Blue Creek *
OK520810000080_00 Little River *
OK520810000090_00 Rock Creek *
OK520810000100_00 Elm Creek
Primary Body Contact Recreation
Warm Water Aquatic Community
Agriculture
E. coli
turbidity
total dissolved solids
OK520810000110_00 East Elm Creek Warm Water Aquatic Community low DO
OK520810000120_00 East Elm Creek *
OK520810000140_00 West Elm Creek *
OK520810000150_00 Kitchen Creek *
OK520810000160_00 Kitchen Lake *
OK520810000170_00 North Fork Little River *
OK520810000175_00 Moore Creek Agriculture total dissolved solids
OK520810000180_00 Mussel Shoals Lake Creek *
OK520810000190_00 Mussel Shoals Lake *
*insufficient information or not assessed
Oklahoma Water Resources Board (OWRB) studies on Lake Thunderbird have shown
that chlorophyll­a
levels are high, thus indicative of the excessive algae growth causing
taste and odor problems for the City of Norman water supply. In 2000, over one­half
of
the water samples collected by the OWRB had chlorophyll­a
concentrations greater
than 20 μg/L (OWRB 2003). The chlorophyll­a
concentration was reduced in 2002, after
aeration of the lake ceased, but the lake still had chlorophyll­a
levels high enough to
cause eutrophication. BUMP data collected from 2001­2003
showed an average
chlorophyll­a
concentration of 30.8 μg/L.
Algae species which are known to cause taste and odor problems in drinking water are
present in the lake, and two potentially toxic algae have been noted in Lake Thunderbird
as well. The concentrations of these algae in the lake corresponded to a low to
moderate risk from direct exposure or accidental ingestion in 2001 and low risk in 2002.
This risk was for recreational exposure, with no evidence of risk noted for water supply
(OWRB 2003). Reducing the amount of nutrients entering the lake is necessary to
decrease the algal concentrations.
Sources
There are no point sources in the Lake Thunderbird watershed; hence, nonpoint
sources are the primary contributors to the pollution problems in this watershed.
Nonpoint sources are those which supply pollutants to surface water diffusely, rather
than as a definite, measurable quantity at a single location. These sources typically
Lake Thunderbird WBP June 2010
­13
­involve
land activities that contribute bacteria, sediment, and/or nutrients to surface
water as a result of runoff during and following rainfall.
Urban Land Use:
The primary sources of pollution in the Lake Thunderbird watershed are associated with
urban expansion and the accompanying development. As urbanization progresses,
runoff from impermeable surfaces and from construction areas (both housing
developments and road construction) are increasingly contributing to nutrient and
sediment loading from the watershed. Water quality is being severely impacted by
increasing runoff volume and velocities, which cause increased erosion of streambanks,
destruction of instream and riparian habitat, and siltation, as well as increased nutrient
loads. Improper use of fertilizers or over­fertilization
may increase with the expected
population growth in the watershed and contribute to the pollution of lakes and
groundwater through loading of soluble and particulate phosphorus as well as nitrogen.
Bacteria and nutrients from domestic pets will be expected to increase as well with the
expected increase in population growth. According to Vieux (2007), urban runoff should
be considered as an increasing, highly significant nonpoint source of pollution in this
watershed.
Vieux and associates performed a study in the Rock Creek watershed, a tributary to
Lake Thunderbird (COMCD 2006). Based on monitoring and analysis of water quality
data in Rock Creek, it was determined that a higher level of nutrients was found in
runoff from developed versus undeveloped land. Vieux’s modeling efforts of the entire
Lake Thunderbird watershed in 2007 supported this finding, indicating that the areas of
the watershed contributing the greatest phosphorus (the limiting nutrient of the lake)
load per unit area were the highly urbanized areas of Moore and Oklahoma City, as well
as a small portion of Norman immediately north of the lake (Figure 4).
Figure 4. Location of total phosphorus sources and yields (kg/hectare) in the
Lake Thunderbird Watershed as determined from SWAT modeling (Vieux 2007).
Lake Thunderbird WBP June 2010
­14
­Similarly,
the greatest sediment load is coming from Moore and the west side of
Norman, followed by the Oklahoma City area (Figure 5).
Figure 5. Location of sediment sources and yields (kg/hectare) in the
Lake Thunderbird Watershed as determined from SWAT modeling (Vieux 2007).
The Rock Creek study (COMCD 2006) indicated that the greater loading of nutrients
from developed areas was due to increased impervious surface and increased
fertilization in urban areas. Vieux’s 2007 SWAT modeling also suggested that
imperviousness was a key factor affecting loading rates in the watershed. It is expected
that continued conversion of agricultural land to residential land will more than double
the phosphorus load to the lake, increasing from an average of 25 kg/ha currently to 54
kg/ha in the future (assuming a build­out
scenario with conversion of 50% of agricultural
areas to residential). Figure 6 shows the areas which are expected to experience the
greatest increases in impervious surface under a build­out
scenario.
Figure 6. Percent change in impervious area from baseline (current levels) to build­out
(projected
conversion of 50% of agricultural lands to residential) (Vieux 2007).
Lake Thunderbird WBP June 2010
­15
­Based
on Vieux’s SWAT model calculations, the total average phosphorus load to Lake
Thunderbird is between 18,000 kg/yr and 23,000 kg/yr. According to Figure 4, the
highest phosphorus loading is occurring in the watersheds of the North Fork of the Little
River and Moore Creek on the west side of the lake, as well as Hog Creek on the east
side of the Thunderbird watershed. The Moore and Norman areas on the west side of
the watershed are contributing the highest sediment load, especially in the headwaters
of Little River, the North Fork of the Little River, Moore Creek, and Rock Creek (Figure
5).
While there are no point source discharges in the Lake Thunderbird watershed,
“bypass­discharges”
from municipalities may occur due to overflows or sewer main
breaks. Several of these events have occurred within the watershed. For example,
from June 2004 to August 2006, the sum of these discharges was:
City of Moore 59,930 gallons discharged to Little River
City of Norman 44,483 gallons discharged to Little River
According to Vieux (2007), raw sewage contains approximately 4­15
mg/L of water­soluble
phosphorus, equating to 2­5
kg of phosphorus over that two year period. This is
not considered a significant amount relative to the overall phosphorus entering the
watershed. The City of Norman completed a wastewater treatment plant (WWTP)
upgrade in March 2010, which should reduce the number of failures in the future. The
hydraulic capacity of the plant has increased from 45,000m³ a day to nearly 100,000m³
a day.
Permitted Sources:
Nonpoint source permitted
activities within the watershed
include 12 total retention lagoons
(Figure 7). Total retention lagoons
hold solid and liquid wastes prior to
land application and may leak or
overflow, thus affecting water
quality.
In addition, there are over 300 oil
and gas permits in the watershed,
located on approximately every
section in the watershed. Not all of
the permitted wells are active;
however, oil and gas operations
could be a potential source of high
TDS values as well as turbidity
sources.
Figure 7. Location of permitted total
retention lagoons and oil/gas wells.
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$
$
$
$
$
$ $
$
$
$
$ $
$
$
$ $
$
$
$
$
$
$
$
$
$ $
$
$
$
$ $
$
$
$
$
$
$ $
$
$
$
$
$ $
$
$
$
$
$
$
$
$
$
$
$
$
$
$
$
$
$
$
$
$
$
$
$ $
$
$
$
$
$
$
$
$
$
$
$
$ $
$
$ $
$ $
$
$ $
$
# Total Retention Lagoons
$ Oil and Gas Wells
Lake Thunderbird WBP June 2010
­16
­Rural
Land Use:
Pasture/forage land is the prevalent rural land use in the watershed. Cattle are the
dominant animal industry in Oklahoma and Cleveland Counties (Table 4). Livestock
grazing in pastures deposit manure, making it possible for the nutrients and bacteria to
enter surface water with runoff. In addition, livestock often have direct access to
waterbodies providing a concentrated source of loading directly into streams. Animals
loafing in the stream also contribute to turbidity problems by stirring up sediment, and
their travels to and from the stream erode banks and carve trails which serve as direct
conduits for NPS contribution during runoff events.
Table 4. Livestock in Oklahoma and Cleveland Counties (USDA Census 2002).
Livestock County Number of animals
Cattle and calves OClkelavheolamnda 2216,,592825
Horses and ponies OClkelavheolamnda 34,,034800
Layers 20 weeks old and older OClkelavheolamnda 12,,472748
Hogs and pigs Cleveland 2,267
Goats Oklahoma 1,696
Sheep and lambs Oklahoma 1,402
Despite the large number of animals, particularly cattle, in these counties, agriculture in
the Lake Thunderbird watershed is largely in the form of small, urban ranchettes, where
landowners have 5­20
acres to keep a few horses or a small herd of cattle. Preliminary
results from Vieux (2007) suggest that, although these areas contribute to overall
loading, urban sources dominate.
Septic Systems:
Failing septic systems can contribute to pathogen and nutrient problems in both
groundwater and surface waters if leakage or illicit discharge occurs. Any loading of
bacteria into the groundwater can enter surface water through seeps or springs. Failing
septic systems were not likely to be a significant factor in this watershed due to the low
density of septic systems.
Wildlife:
Wild animals which produce fecal bacteria and have direct access to streams include
deer, raccoons, other small mammals, and avian species. Wildlife is considered to be a
minor contributor of pollution in this watershed.
Shoreline / Streambank Erosion:
Lake Thunderbird is experiencing considerable shoreline erosion with cut banks
exceeding 20 feet in height in some locations (OWRB 2001a). Wave action and runoff
on these bare areas are contributing significantly to the turbidity impairment of the lake.
A shoreline erosion control demonstration project was intiated by the OWRB in order to
reduce the amount of suspended sediment in Lake Thunderbird. During 2003, the
OWRB staff installed hundreds of feet of breakwater structures and more than 1,000
aquatic plants along a 450­foot
area of the southern shoreline. It is expected that the
Lake Thunderbird WBP June 2010
­17
­breakwaters
will help settle out sediments and
promote the establishment of beneficial
shoreline vegetation. In addition, the OCC in
partnership with the City of Norman is currently
implementing a project to restore a riparian
buffer along the North Fork of the Little River.
Unstable streambanks could also contribute
significantly to phosphorus loading in the
watershed, especially since streambank soils
are often high in phosphorus.
Lake Thunderbird shoreline erosion control
LOAD REDUCTIONS (element b)
Because of Lake Thunderbird’s impaired status, Total Maximum Daily Load (TMDL)
allocations are required for dissolved oxygen and turbidity. The Oklahoma Department
of Environmental Quality Water Quality Division (ODEQ) is currently working on a
detailed Hydrological Simulation Program Fortran (HSPF) model for the watershed and
has contracted to have an EFDC in­lake
model developed. These two models will be
used to develop a comprehensive TMDL for the lake. Until the release of the TMDL, the
focus of this WBP will be on reducing phosphorus, since data collected and analyzed by
the OWRB indicates that phosphorus is the limiting nutrient in Lake Thunderbird. The
subwatersheds in red in Figure 4 will be the primary targets for implementation projects
since these are the areas supplying the highest phosphorus loads and, thus, should
provide the largest load reductions.
Using a SWAT model, Vieux (2007) calculated that the total average phosphorus load
to Lake Thunderbird is between 18,000 kg/yr and 23,000 kg/yr. This correlates with a
measured average total phosphorus concentration of 0.057 mg/L and chlorophyll­a
concentration of 30.8 mg/L. The primary source of phosphorus loading in the watershed
is urbanization, as shown in Figure 4 and discussed in the previous section. Runoff
from impervious surfaces in urban areas has the highest potential for contributing
pollutants to waterbodies in these areas.
The goal of this WBP is to reduce the nutrient loading to Lake Thunderbird so that the
chlorophyll­a
concentration is 10 mg/L, a 32% reduction. This corresponds to a
reduction of approximately 10,000 kg/yr total phosphorus (58% overall) (Vieux 2007).
This reduction in phosphorus should increase the dissolved oxygen concentration of the
lake, decrease the turbidity, and allow restoration of the WWAC designated use. In
addition, it is expected that measures implemented through this watershed project to
address phosphorus will concomitantly reduce the bacteria loading in Elm Creek and
sediment loading in Moore Creek. However, urbanization is expected to continue in this
watershed, so it is vital to examine the required load reductions in light of future
development plans.
Lake Thunderbird WBP June 2010
­18
­Vieux
(2007) modeled the loads expected if 50% of the agricultural or vacant land was
converted to residential property over the next 30 years. The findings indicate that the
total phosphorus load would be 24,907 kg/yr under these conditions, so a reduction of
approximately 68% (approximately 16,937 kg/yr) would be necessary to achieve the
chlorophyll­a
goal of 10 mg/L in the future. This reduction will be the long­term
goal for
the project.
The following section of the WBP addresses the management measures necessary to
achieve these present (short­term)
and future (build­out)
load reductions. After the
release of the TMDL for Lake Thunderbird, most likely in 2011, management measures
and load reduction goals described in this WBP will be updated based on the
recommendations of the TMDL.
NPS MANAGEMENT MEASURES (element c)
SWAT modeling has allowed for estimation of nutrient load reductions expected from
certain management measures (Vieux 2007). The results of this modeling effort show
that Best Management Practices (BMPs) should focus on reduction of nutrient loading
from urban nonpoint sources. Implementation of such practices is expected to achieve
an initial NPS phosphorus load reduction goal of 58% and is likely to significantly
improve the turbidity, bacteria, and dissolved oxygen issues in the lake and streams.
It is recognized that not any one activity could realistically result in the required
reduction; instead, numerous strategies will have to work together to achieve the
desired result. With this in mind, this document is not intended as a final, static plan,
but rather one that will be updated as needed to reflect new information, resources, and
necessary adjustments in implementation strategy.
The initial watershed implementation program will focus on
facilitating Low Impact Development (LID) techniques in the
watershed. A local developer has partnered with OCC to
implement and assess LID practices in a new residential
development, titled the Trailwoods Project. For this project, 18
houses will be built along a street with rain gardens to filter
stormwater runoff from the street (dark green in Figure 8) while 18
houses will be built
on an adjoining
street with
conventional curbs
and street gutters to
convey stormwater.
The OCC will install
autosamplers for
continual monitoring
and assessment of
Figure 8. Street design (LID side) of Trailwoods project (left), and
location of the neighborhood in the watershed (right).
Lake Thunderbird WBP June 2010
­19
­the
runoff of both streets. This project will be primarily a demonstration and research
project. Results will be presented to City of Norman officials in the hope that more
projects like this will be approved.
Before more broad­reaching
projects can be tackled, a significant portion of the
implementation strategy will be to work with cities in the watershed to revise their
building codes as needed to allow for construction of LID systems. Special approval
was granted for the Trailwoods project from the City of Norman. OCC will compile and
review examples of existing codes from nearby communities that support LID and
provide for water quality friendly construction techniques. These examples will be
presented to the watershed cities for possible incorporation into their municipal codes.
In addition, OCC will send city planners from the area to LID workshops and related
training such as the one offered by the Water Conservation Resource Center in
Fayetteville, Arkansas. OCC will also organize and facilitate tours of LID
implementation in nearby areas to demonstrate possibilities for the city planners and
relevant personnel. Since most of the project area is incorporated and zoned, the OCC
will also work with municipalities to achieve pollution control through zoning and
ordinance regulations.
Vieux’s modeling results clearly indicate the subwatersheds contributing the greatest
loads currently, as well as those where the greatest future load is expected (Figures 4,
5, and 6). These urban areas of the watershed will be targeted for the initial
demonstration of low­impact
development (LID) so that the most efficient load
reductions can be accomplished. Examples of urban practices that will be suggested
are given in Table 5. The efficiency of each of these practices in removing phosphorus
is included in the table, as well as the practical application and constraints associated
with each practice. Combining certain types of practices and implementing them
throughout the watershed could result in reductions in total phosphorus load beyond the
required reduction to meet the chlorophyll­a
goal of 10 mg/L (Vieux 2007). Initial
implementation will be focused in the subwatersheds with the highest phosphorus
loading (Figure 4). As mentioned previously, these areas are the most developed and
actively developing areas in the watershed, so it will be vital to work with officials from
Norman, Moore, and Oklahoma City to get approval for LID implementation.
An additional strategy for in­lake
reduction in
sediment and nutrient loads would be to work with
management authorities to institute new/amended
boat traffic limitations. Because of its proximity to
the urban community, Lake Thunderbird
experiences particularly heavy powered boat traffic,
which is thought to contribute significantly to
shoreline erosion and thus nonpoint delivery of
sediment and nutrients. Lake­wide
limitations on
engine size and/or speed restrictions could aid in
reducing this problem.
Urban raingarden
Lake Thunderbird WBP June 2010
­20
­Table
5. Possible management practices for urban areas. Highlighted rows are practices recommended for this project by Vieux (2007).
Best
Management
Practice
Phosphorus
Removal
Efficiency
Maintenance Required Other Benefits Problems Applicable Landuse
Conditions
Sediment
Forbay
Required to
achieve
Phosphorus
removal efficiency
for structural
practices.
Sediment should be removed every 3­5
years or when 6­12
inches have accumulated, whichever occurs first. To
reduce maintenance costs, an on­site
sediment disposal
area should be included in the design.
Improves phosphorus and sediment removal
efficiency of primary MPs. Facilitates
maintenance of MPs and extends the "life
expectancy" of primary management practice.
Phosphorous removal efficiencies are
based on the inclusion of sediment forbays
in the project design.
Required to improve efficiency and life span
of most other management practices. Also
facilitates maintenance of other
management practices.
Vegetated
Filter Strip 10%
Requires regular maintenance. This management
practice usually has short life span due to lack of
maintenance, improper location, and poor vegetative
cover. Maintenance includes inspections, fertilizing,
watering, and re­planting.
Also repair from gully erosion,
traffic, and concentrated flow. After established (several
years), maintenance requires removal of accumulated
sediment, reestablishing vegetations, weeding invasive
weeds, pruning woody growth.
May also result in reduction of nitrogen in
storm water.
For Overland Sheet Flow!!! Max
contributing area 5 acres. From Center for
Watershed Protection (1996), runoff
changes from sheet flow to concentrated
flow after traveling 75 feet on impervious
surfaces and 150 on pervious surfaces.
Requires soils with infiltration rate of 0.52
in/hr (sand and sandy loams).
Residential (16­21%)
impervious or as a
pretreatment component to structural
management practices.
Grassed
Swale 15% Maintain thick vegetation at 3­6
inches. Remove debris,
and sediment, and re­establish
vegetation if needed.
Excellent for residential areas. Requires
matenance agreements included in land titles.
Maintenance responsibility of each land owner.
(Monograph 14, pg 400) ­Cost
effective
compared to concrete gutters and efficient
sediment removal.
Landowners are likely to mow the grass in
the swale too short reducing pollutant
removal efficiency. Requires soils with
infiltration rates of 0.27 in/hr (silty loams) or
better.
Residential 16­21%
impervious cover. If
water quality swales are incorporated, will
work with higher density development up to
37% impervious area.
10% with
voluntary reduction
May be difficult to obtain "buy­in"
from the
community. Requ Urban ires annual soil testing.
Nutrient
Management Up to 22% with
statutory reduction
Urban nutrient management involves the reduction of
fertilizer (especially phosphorus) to grass lawns and other
urban areas. Implementation of urban nutrient
management is based on public education and
awareness, with emphasis on reducing excessive fertilizer
use.
May also result in reduction of nitrogen in
storm water. Requires implementing an ordinance such
as the Minnesota Phosphorus Lawn
Fertilizer Law.
Percent impervious cover 16­21%.
Constructed
Wetlands
30%
Second season reinforcement plantings are often
needed. Mow biannually to reduce woody growth on outer
boundary. Maintain sediment forbay. Pretreatment
management practices will reduce the cost of
maintenance and the effective life expectancy of the
constructed wetland. Remove sediment from forbay every
3­5
years or when 6­12
inches of sediment has
accumulated.
High removal rate of particulate and soluble
pollutants (nutrients) and sediment. Wildlife
preservation. Bird watching.
Permeable soils are not suited for
wetlands construction. Requires large land
areas (2% of the size of the contributing
watershed).
Percent impervious cover 22­37%.
Basin
requires minimum drainage of 10 acres and
may not be located near (within 100 feet) of
septic systems. Permeable soils are not
suited for constructed wetlands. May not be
suited for highly visible sites or adjacent to
highly manicured sites.
Extended
Detention
Basin
(2xWQ Vol)
35%
Mow 2x's per year; remove debris from spill way and
trash rack at control structure; and maintain sediment
forbay.
Excellent option for watershed approach.
Function as designed for long periods without
routine maintenance.
Not aesthetically pleasing. Requires 20
foot vegetative buffer. Drainage areas over
50­75
acres require provisions for base
flow. Not suitable for highly permeable
soils.
Percent impervious cover 22­37%.
Low
visibility sites. Appropriate for regional or
watershed approach.
Extended
Detention­Enhanced
50%
Mow two times per year; remove debris from spill way
and trash rack at control structure; and maintain sediment
forbay.
The enhanced extended detention basin has a
shallow marsh which provides additional
pollutant removal and reduces re­suspension
of
settled pollutants. To increase the phosphorus
removal of the extended detention basin one
must increase the volume of the marsh. Wildlife
habitat and associated recreation.
Not aesthetically pleasing. Requires a 20
foot vegetative buffer. Drainage areas over
50­75
acres require provisions for base
flow. Not suitable for highly permeable
soils.
Percent impervious cover 38­66%.
Lake Thunderbird WBP June 2010
­21
­Best
Management
Practice
Phosphorus
Removal
Efficiency
Maintenance Required Other Benefits Problems Applicable Landuse
Conditions
Retention
Basin I
(3XWQ Vol)
40%
Mow two times per year; remove debris from spill way
and trash rack at control structure; maintain sediment
forbay. Aeration may be needed in Oklahoma.
High nutrient, sediment and phosphorous
removal efficiencies. Can help with flood control
and downstream channel erosion when
coordinated within a Watershed Management
Plan.
Increase water table. Needs to be part of
"watershed management plan" as too many
detention/retention basins in a basin can
severely alter the natural flow conditions
with combined peak flows and increased
flow durations, resulting in downstream
flooding and stream channel degradation.
Percent impervious cover 22­37%.
Basin
requires minimum drainage of 10 acres and
not located near (within 100 feet) of septic
systems. Permeable soils are not suited for
retention basins.
Retention
Basin II
(4xWQ Vol)
50%
Mow two times per year; remove debris from spill way
and trash rack at control structure; maintain sediment
forbay. Aeration may be needed in Oklahoma.
High nutrient, sediment and phosphorous
removal efficiencies. Can help with flood control
and downstream channel erosion when
coordinated within a Watershed Management
Plan.
Increase water table. Needs to be part of
"watershed management plan" as too many
detention/retention basins in a basin can
severely alter the natural flow conditions
with combined peak flows and increased
flow durations, resulting in downstream
flooding and stream channel degradation.
Percent impervious cover 22­37%.
Basin
requires minimum drainage of 10 acres and
not located near (within 100 feet) of septic
systems. Permeable soils are not suited for
retention basins.
Retention
Basin III
(4xWQ Vol
with aquatic
bench)
65%
Mow two times per year; remove debris from spill way
and trash rack at control structure; maintain sediment
forbay. Aeration may be needed in Oklahoma.
High nutrient, sediment and phosphorous
removal efficiencies. Can help with flood control
and downstream channel erosion when
coordinated within a Watershed Management
Plan.
Increase water table. Needs to be part of
"watershed management plan" as too many
detention/retention basins in a basin can
severely alter the natural flow conditions
with combined peak flows and increased
flow durations, resulting in downstream
flooding and stream channel degradation.
Percent impervious cover 22­37%.
Basin
requires minimum drainage of 10 acres and
not located near (within 100 feet) of septic
systems. Permeable soils are not suited for
retention basins.
Bioretention
basin or
Rain
Gardens
50%
Annual soil pH testing and application of lime to adjust
pH; routine mulching and maintenance of plant material.
Removal of hazardous and toxic soil/plant material
required when the system "dies".
Degradation of oily pollutants, clay absorbs
heavy metals, nutrients and hydrocarbons.
Reduce peak discharge and provides
groundwater recharge. Accumulation of toxins
and heavy metals within 5 years.
Requires permeable soil! Life expectancy
as little as 5 years. May require removal of
infiltration media and plant material.
Percent impervious cover 38­66%.
Highly
visible development. Residential to fairly
high density commercial projects.
Bioretention
filter
50%
Annual soil pH testing and application of lime to adjust
pH; routine mulching and maintenance of plant material.
Removal of hazardous and toxic soil/plant material
required when the system "dies".
Filter is connected to storm sewer which can
lead to structural or other primary management
practices.
Requires permeable soil. Life expectancy
as little as 5 years. May require removal of
infiltration media and plant material when
the system dies. This material may be
classified as hazardous or toxic upon
removal.
Percent impervious cover 38­66%.
Infiltration
(1 x WQ Vol) 50%
Inspection monthly and after large storm events until
operations are stable. After the system is stable, inspect
semi­annually
and after large storm events. Control
sediment and maintain vegetation.
Reduce peak discharge and provide
groundwater recharge
Does not control large volumes of run­off,
works for 2­year
design storm. Requires
permeable soil and lower water table. Does
not work for oily sites due to clogging from
sediment, oil, and grease.
Percent impervious cover 38­66%.
Not
suitable for roadways, parking lots and car
service facilities unless a settling basin or
"cell" is used for pretreatment.
Infiltration
(2xWQ Vol) 65%
Inspection monthly and after large storm events until
operations are stable. After the system is stable, inspect
semi­annually
and after large storm events. Control
sediment and maintain vegetation.
Reduce peak discharge and provide
groundwater recharge
Does not control large volumes of run­off,
works for 2­year
design storm. Requires
permeable soil and lower water table. Does
not work for oily sites due to clogging from
sediment, oil, and grease.
Percent impervious cover 38­66%.
Not
suitable for roadways, parking lots and car
service facilities unless a settling basin or
"cell" is used for pretreatment.
Sand Filter 65%
Properly sized filters have a life span of up to 20 years.
However, the top few inches of sand needs to be replaced
every 3­5
years. Requires accessibility (manholes) for
vacuum trucks.
Removal of heavy metals, BOD, nutrients, and
hydrocarbons. Aerobic filters enriched with iron
may attain nearly complete removal of
phosphorus. Can be placed underground.
Subject to failure by clogging by sediment
and heavy hydrocarbon loads.
Underground vaults are classified by OSHA
confined spaces. Will not function properly
if subjected to continuous or frequent flows.
Essential to exclude flow containing
chlorine (such as pool water).
Ultra­urban
settings with percent impervious
cover 67­100%.
Suited for high pollutant
removal on medium to high density
development. Not suitable for basins with
high sediment loads due to clogging.
Lake Thunderbird WBP June 2010
­22
­Vieux
(2007) found that the Little River Arm of
Lake Thunderbird reduced the phosphorus load
to the main body of the lake by 36% by allowing
sediment and the phosphorus bound to it to
settle as the water velocity decreases upon
entering this area. It is possible that increasing
the residence time of sediment in shallow arms
of the lake such as this may significantly
improve water quality. One of the tasks in the
current OCC project will be to create a wetland
development plan for the Upper Little River
(above the bridge) and Hog Creek arms to
promote more extensive settling of sediment
and associated nutrients before entering the lake Figure 9. Potential wetland development
(Figure 8). sites.
The City of Norman has recently completed a 682 page, comprehensive “Storm Water
Master Plan” (SWMP) which considers issues such as water quality, creek corridor
environmental features, creek erosion / stabilization, and greenbelt / open space
expansion opportunities at a very detailed subwatershed level. One of the goals of the
plan is “to protect natural creek riparian environments, as well as comprehensively
managing floodplains to include recreational opportunities, trails and open spaces”
(Cole 2007). This document describes 12 subwatersheds in great detail, including
proposed BMPs to address problems causing flooding and stream erosion. The
establishment and expansion of riparian buffers is one of the top recommendations for
improving water quality and addressing flooding in the city. The City of Norman realizes
that the restoration of the bottomland
hardwood forest and riparian wetlands that
once were widespread along the Little River
and its tributaries could improve overall
quality of the lake. In addition, streambank
stabilization projects and LID are to be
encouraged. The OCC is currently
cooperating with the City in a streambank
stabilization project and hopes to participate
in the development of different aspects of the
larger SWMP. The entire SWMP may be
viewed at this link:
http://www.ci.norman.ok.us/sites/default/files/WebFM/Norman/Public%20Works/Storm
WaterMasterPlanFinalDraft.pdf
Oversight of OCC project activities will be the responsibility of the Project Coordinator
with assistance from the City of Norman, the Cleveland County Conservation District,
and additional OCC staff. This WBP will be presented to cities, developers, and other
appropriate groups in the watershed in an attempt to further the adoption of these
practices. Activities in the watershed will be designed to complement projects that the
Cleveland Co.
Oklahoma Co.
Hog Cr.
Kitchen Cr .
West Elm Cr
Elm Cr.
Little Riv e r
North F ork Lit tle
M oore Cr.
Rock Cr.
Dav e B lue Cr.
Clear Cr.
Jim Blue Cr.
West Hog C
L. Stanley Draper
Lake Thunderbird
0 5
Proposed wetland
development
sites
Little River in Norman
Lake Thunderbird WBP June 2010
­23
­cities
have planned, for example, those detailed in the City of Norman SWMP.
Soil tests may be offered as part of this project in order to reduce nutrients in runoff from
lawns, gardens, parks, and golf courses in the watershed. The average soil test
phosphorus (STP) level of lawn and garden soils in Oklahoma is several times higher
than that required by plants. This suggests that too much fertilizer and/or incorrect
fertilizer formulas are being used for those areas. Studies have shown that dissolved
reactive phosphorus (which is linked to algae blooms directly) in the runoff from lawn
and golf courses increases as STP and fertilizer rates increase. Education efforts will
be tied to soil test results so that proper fertilizer application is emphasized.
Vieux modeled several combinations of BMPs that would result in the necessary
reduction in total phosphorus (TP) loading to achieve a chlorophyll­a
concentration
below 10mg/L. As shown in Table 6, below, constructing wetlands and installing some
structural controls would reduce TP loading by 66%, and if coupled with fertilizer
reductions, these BMPs are expected to result in the appropriate decrease in TP and,
subsequently, chlorophyll­a.
Table 6. Impact of targeted BMPs on percent reduction of total phosphorus (TP), TP loads, TP
concentration, and chlorophyll­a
concentration.
The small acreage size managed by the typical agricultural producer, coupled with the
respectively large number of small landowners, adds to the difficulty of significantly
reducing loads from agricultural areas in this watershed. In the future projects,
agricultural BMPs may be funded, including: (1) riparian area establishment to include
fencing, vegetative establishment, off­site
watering, livestock shelters and incentive
payments; (2) streambank stabilization to include fencing and vegetative plantings; (3)
animal waste storage facilities / heavy use areas; and (4) pasture management /
pasture establishment. Cooperation with NRCS in Cleveland and Oklahoma Counties
may allow expansion of EQIP and CSP programs (CSP began in 2005 in this area as
part of the Little River priority watershed) which include practices to reduce soil erosion
and improve livestock watering facilities.
The OWRB conducted a shoreline erosion control demonstration project at Lake
Thunderbird through EPA’s §319 NPS program. Depending on the success of this
project, other similar projects may be implemented in the lake to reduce lake margin
Lake Thunderbird WBP June 2010
­24
­sediment
contributions. Through this project, the OWRB seeks to educate lake
managers on the benefits of establishing aquatic plants to improve the health of the
aquatic community and reduce erosion.
In addition, the OWRB and COMCD have partnered to install an aeration system in the
lake to increase the dissolved oxygen and improve overall water quality. The project
will withdraw water from the lake bottom, oxygenate it to 300% (310 mg/l), and return
the supersaturated water back into the lower lake layer, restoring the dissolved oxygen
to levels that will allow attainment of the designated uses and reduce summer
chlorophyll­a
levels. Funding ($692,773) for this effort was derived from the Oklahoma
Water Resources Board’s Clean Water State Revolving Fund obtained through the
American Recovery and Reinvestment Act of 2009. The aerator is scheduled to begin
operating in the summer of 2010.
BMPs, planned and implemented, will be tracked for future watershed modeling and for
reporting project performance. Project staff will make regular site visits to assess
progress in implementing planned BMPs. Details will be summarized in the project final
report.
PUBLIC OUTREACH (element e)
Much of the initial focus of the WBP will involve educating personnel and changing city
ordinances. This section identifies agencies, organizations, and services that are
already active in the watershed or that will be collaborators in the Lake Thunderbird
watershed. These groups will help develop the WBP and assist in other planning efforts
in the watershed to varying degrees. Cooperation and implementation by cities in the
watershed is imperative to achieve the water quality improvement goals.
The specific roles of the groups and programs which are likely to contribute to the public
outreach efforts in the Lake Thunderbird Watershed are summarized in no particular
order below:
1. Local Conservation District Offices
The Cleveland County Conservation District will provide substantial support for
the implementation of this project. The Oklahoma County Conservation District
will also provide support for the project, but to a lesser degree than Cleveland
County due to difference in district area in the watershed. The Districts may
participate in educational activities such as seminars, training sessions, and
meetings to interact with local people and provide technical assistance and
information.
2. Municipalities
Cities in the watershed maintain active, well­developed
education programs.
However, education programs are rarely funded to a level that meets existing
needs and can always use additional technical support and other resources. The
Lake Thunderbird WBP June 2010
­25
­Lake
Thunderbird education program will supplement rather than replace the
existing education programs in the watershed in cooperation with local
stakeholders. The City of Norman specifically plans to establish a program to
educate residents about fertilizer usage.
3. OCC Education Programs
The education component of the Lake Thunderbird Watershed Implementation
Project will be developed around the following goals:
(1) Work within the MS4 coordinators of Moore, Norman, and Oklahoma City to
assist their programs with NPS pollution education.
(2) Educate city staff about low impact development, nonpoint source pollution,
water quality, and water conservation.
(3) Involve cities and residents in the targeted areas in education programs
designed to explain the water quality problems and what can be done to
reduce potential impacts.
(4) Write frequent articles for area newsletters and/or newspapers about project
activities.
(5) Work with Conservation Districts on a Blue Thumb program in the watershed.
(6) Develop a display for the project that can be used to educate the public on
the 319 Program. Display should include basic information on the program,
its cooperators, and contact people of ongoing programs in the watershed.
(7) Track how participation in the education program has changed people’s
behaviors. Project coordinator will follow five to ten percent of people
intercepted through different aspects of this and related project activities and
will contact them on an annual basis throughout the project period to
determine whether they have made any changes that would affect NPS
pollution.
(8) Plan and conduct educational meetings to include: tours, earth days, fairs,
etc. These education programs will be designed to explain the water quality
problems and what can be done to reduce potential impacts, both agricultural
and urban.
(9) Coordinate education of public on nutrient management and water quality
through the Master Gardener Programs of Oklahoma and Cleveland
Counties. Master Gardeners will be educated on water quality issues and
technologies. They will participate in the bioretention cell program by helping
to evaluate the performance of vegetation in the rain gardens and by
explaining their performance to the public. The Master Gardeners will also
conduct demonstrations for the public at visible locations and at public
functions like the County Fair and other events.
Initially, the OCC will organize and hold one regional LID workshop through the Institute
for Quality Communities. This will allow for in­depth
education on stormwater BMPs
and allow civic officials training in Oklahoma and the south­central
plains region. The
OCC will provide educational programs as part of other projects in the watershed as
well. For instance, as part of a 2003 Riparian Area Restoration project, three seminars,
targeted at City planners, local officials, and students of various ages, will be held to
Lake Thunderbird WBP June 2010
­26
­relate
the importance of riparian wetland areas within urban and rural environments.
Demonstration of riparian management practices will also be part of the education
program for this project.
In general, youth education is a significant effort that will be pursued in the Lake
Thunderbird watershed. Most youth education activities focus on general water quality
maintenance and improvement and include activities such as 4­H
group water quality
monitoring and education, “Earth­Day­Every­Day”
activities fair where hundreds of
elementary school children and some of their parents are exposed to environmental
education, and various other training sessions. Blue Thumb educators will play an
important role in youth education in this watershed.
The success of water quality protection programs in the watershed depends on the
approval and cooperation of the local landowners and various government agencies. In
summary, public outreach to assure support of this and future evolutions the Watershed
Based Plan will come from:
· Regular media coverage of activities/issues (both at local and State levels).
· Education programs that involve segments of the community ranging from school
children to agricultural producers to homeowners.
· Programs that encourage local citizens to experience “ownership and
understanding” of environmental issues such as volunteer monitoring, clean­up
events, and other educational grassroots efforts to address the problem.
The goal of the public outreach portion of this project is to develop a program that will
help the citizens of the Lake Thunderbird Watershed reduce NPS pollution.
CRITERIA to DETERMINE PROGRESS (element h)
The ultimate goal of this WBP is to reduce the nutrient loading to Lake Thunderbird by
approximately 10,000 kg total phosphorus per year, as well as reduce the pathogen and
sediment loads in the tributaries to the lake, so that all designated uses of waterbodies
in the watershed are fully attained. These goals are guided by the water quality criteria
described in this section, all of which are based on Oklahoma’s Water Quality
Standards (OWRB 2008). However, in 2000, the COMCD, OWRB, and the three
municipalities receiving water from Lake Thunderbird (Norman, Midwest City, and Del
City) set goals for an upper limit of 20 μg/L of chlorophyll­a
for open water sites during
the growing season (OWRB 2001b). This will be an interim target for improvement in
the lake.
Lake Thunderbird’s designated beneficial uses include Aesthetics, Agriculture, Warm
Water Aquatic Community, Primary Body Contact Recreation, Public and Private Water
Supply, Fish Consumption, and Sensitive Water Supply. The tributaries to Lake
Thunderbird have these same designated uses, with the exception of Moore Creek,
which does not have the Sensitive Water Supply designation. Only the criteria for the
listed causes of impairment (from Table 3) are presented below, along with the criteria
Lake Thunderbird WBP June 2010
­27
­for
the Sensitive Water Supply (SWS) and Nutrient Limited Watershed (NLW)
designation.
To determine attainment of the Primary Body Contact Recreation use (for streams),
samples must be collected during the recreation season, from May 1­September
30,
and at least ten samples are required to make an attainment assessment.
To attain the PBCR use:
· Escherichia coli (E. coli)
a) No sample shall exceed 406 colonies/100 ml.
b) Monthly geometric mean must be less than 126 colonies/100 ml.
To attain Warm Water Aquatic Community use:
· Turbidity (only applicable during baseflow)
a) No more than 10% of samples will exceed 25 NTU (for lakes).
b) No more than 10% of samples will exceed 50 NTU (for streams)
· Dissolved oxygen (DO)
a) No more than 50% of the water column at any given sample site in a lake
or an arm of a lake will be below 2 mg/L due to other than naturally
occurring conditions (for lakes).
b) No more than 10% of samples will be below 5 mg/L, or 4 mg/L from June
16­October
15, based on at least 10 samples (for streams).
A minimum of ten samples is required to make an attainment determination for any
agriculture parameter. To attain the Agriculture use (for streams):
· Total dissolved solids (TDS)
a) Samples shall not exceed 700 mg/L. If any sample exceeds 700 mg/L,
then the yearly mean shall not exceed 265 mg/L, and no more than 10%
of the samples shall exceed 294 mg/L (values specific to waterbody
segment 520810).
Sensitive Water Supply designation:
The "sensitive water supply" (SWS) designation means that new point source
discharges of any pollutant and increased load of any pollutant from any point source
discharge shall be prohibited in these waterbodies or watersheds unless the discharger
“demonstrates to the satisfaction of the permitting authority that a new point source
discharge or increased load from an existing point source discharge will result in
maintaining or improving the water quality of both the direct receiving water and any
downstream waterbodies designated SWS.” In addition, a waterbody designated SWS
shall not have long­term
average concentrations of chlorophyll­a
at 0.5 meters below
the lake surface of greater than 10 mg/L.
Nutrient Limited Watershed designation:
A nutrient limited watershed is one in which a designated beneficial use is adversely
affected by excess nutrients as determined by Carlson’s Trophic State Index using
chlorophyll­a
of 62 or greater.
Lake Thunderbird WBP June 2010
­28
­All
of the above criteria stem from Oklahoma’s Water Quality Standards (OAC 785:45,
OWRB 2008). Attainment of these criteria will indicate full success of the WBP. The
procedures by which the data must be collected and analyzed to verify whether or not
these criteria have been met are identified in Oklahoma’s Use Support Assessment
Protocols (OAC 785:46, OWRB 2008). Progress toward achieving these criteria will be
gauged through monitoring by both the OWRB (in­lake
data) and the OCC (stream
data).
Any improvement in the parameters described above will be considered indicative of
success in the watershed. It is expected that complete attainment of the water quality
criteria will not occur for several years after implementation of BMPs, especially in the
lake itself, since there is a lag time between BMP implementation and observable water
quality changes, especially in large waterbodies. After release of the TMDL, more
specific interim criteria can be set.
For the initial LID project, the OCC will compare water quality from runoff events in the
control side of the neighborhood (built with conventional curbs and storm drains) to the
LID side of the neighborhood (built with rain gardens to filter runoff from the street and
lots). The effect of this single project in the watershed is expected to be small; however,
the results of this monitoring (details in a later section) will be used to guide future LID
projects in the watershed.
As future projects are implemented by the OCC or other entities, the WBP will be
updated, and expected load reductions will be calculated. Data from ambient
monitoring in the watershed will be assessed on a regular basis and compared with
modeling results to determine whether revisions are necessary.
IMPLEMENTATION SCHEDULE and INTERIM MILESTONES (elements f and g)
Education, implementation, and demonstration of BMPs should reduce the overall load
of nutrients, sediment, and bacteria entering the waterbodies of the Lake Thunderbird
watershed and ultimately reaching the lake. Implementation of best management
practices will focus on low impact development in urban areas as well as some riparian
reestablishment and stream bank protection. The effects of implementation programs in
the watershed on bacteria, nutrient, and sediment loading from the various sources will
be evaluated at the end of the project as well as every five years to determine the future
strategy to be followed. This Watershed Based Plan will be revised approximately
every two years to reflect new information and address short­comings
identified with
earlier plans.
The initial goal is that at least a fifty­eight
percent total phosphorus load reduction will be
achieved through multiple activities in the watershed. Until this load reduction can be
proven with water quality data, it will be demonstrated by modeling the expected load
reductions from implemented practices. Goals for improvement in dissolved oxygen
and turbidity will be added to the plan once these TMDLs have been completed. Table
Lake Thunderbird WBP June 2010
­29
­7
details the schedule of the goals and actions of the WBP and long­term
load
reductions, as well as some interim activities. The “ultimate total load reduction” goal is
based on the expected 2030 build­out
scenario as described in Vieux (2007).
Table 8 presents interim milestones planned for the current LID project (Trailwoods).
Figure 10 shows the timeline of the Trailwoods project, which will be implemented in two
phases, as denoted by the vertical dashed line in that figure. More specific timeframes
are given in the workplans and QAPPs related to this project.
There is ongoing long­term
monitoring to assess water quality in the lake. The OWRB
will continue to collect water quality data and source information, and the OCC will
install autosamplers to insure that load reductions in the watershed can be measured
throughout the project period. Trend analyses will be performed on the various data
sets (bacteria, turbidity, lake chlorophyll­a
concentrations, TSIs, and nutrient
concentrations and loading) and will be evaluated at three year intervals with the
revisions of the WBP to determine whether measurable changes have occurred in water
quality.
Table 7. Schedule and Load Reduction Goals Associated with Activities Planned.
Goal Action Parameter
to Address
Initial Load
Reduction
Ultimate
Total Load
Reduction
Year to
Begin
Year to
Evaluate
and Adjust
Year to
Complete
SWAT modeling and
targeting
Nutrients,
Sediment complete complete
TMDL development
Dissolved
oxygen,
Turbidity
2008 2011
Characterize
NPS
contributions and
evaluate nutrient
dynamics and
impacts in
watershed Treatment Wetlands
study
Nutrients,
Sediment
NA NA
2010 2013
Compile and review LID
ordinances in nearby
states
complete complete
Send city planners / staff
to LID training workshop 2010 annually
Implement LID tour for
city planners / staff 2011 annually
OCC Blue Thumb
Program ongoing annually ongoing
Education and
outreach
programs
Municipal Stormwater
Programs ongoing ongoing
Trailwoods
319 project 2008 2011 2014
Implement urban
BMPs City of Norman
Stormwater Master Plan
Programs
Nutrients,
Sediment,
Pathogens
58% overall
NPS
phosphorus
load
68% overall
NPS
phosphorus
load
ongoing ongoing
OCC – Trailwoods
project
Nutrients,
Sediment 2011 2014
Water quality
monitoring
programs
Municipal Stormwater
Monitoring
Nutrients,
Sediment,
Pathogens
NA NA
ongoing ongoing
Lake Thunderbird WBP June 2010
­30
­Goal
Action Parameter
to Address
Initial Load
Reduction
Ultimate
Total Load
Reduction
Year to
Begin
Year to
Evaluate
and Adjust
Year to
Complete
OWRB – Beneficial Use
Monitoring Program
Nutrients,
Sediment,
Pathogens
ongoing ongoing
OCC –
Blue Thumb Program
Nutrients,
Sediment,
Pathogens
ongoing ongoing
ODEQ –
TMDL monitoring,
NPDES permitting
Nutrients,
Sediment,
Pathogens
ongoing ongoing
Table 8. Interim milestones for current OCC 319 project (Trailwoods Demonstration Site).
Task Description Time Frame
Investigation of site conditions, regulatory constraints, and
opportunities pertaining to LID practice implementation at the site November 2009
Determine similar sub­basins
within project area and conduct
preliminary planning of neighborhood design and LID BMP
implementation
February 2010
Complete necessary planning and draft conceptual design February 2010
Finalize design and complete construction drawings and BMP
specs May 2010
Implement construction of demonstration neighborhood Projected completion
June 2011
Develop model to assess life cycle costs of selected BMPs
compared to conventional design December 2011
Phase I
BMP Implementation:
Design and Construct
Demonstration
Neighborhood
Update life cycle cost models with actual benefit data realized at
the conclusion of the project period / Final analysis report May 2014
Hold Blue Thumb Training in watershed biannually
Organize and facilitate LID workshop for OK civic officials December 2010
Informational report September 2011
Model LID code September 2013
Organize and facilitate a LID training program for civic officials May 2014
Watershed
Education
Track behavioral change Throughout project
Water Quality Monitoring in Support of TMDL Development QAPP April 2008
Install autosamplers and begin monitoring May 2008
Trailwoods Demonstration Site Monitoring QAPP December 2010
Install autosamplers and begin Trailwoods demonstration site
monitoring January 2011
Update Thunderbird WBP to include ODEQ TMDL modeling results
and recommendations August 2011
Perform analysis of monitoring data – One year post­construction
completion December 2011
Perform analysis of monitoring data – Two years post­construction
completion December 2012
Water Quality
Monitoring /
Assessment
Perform final analysis of monitoring data May 2014
Lake Thunderbird WBP June 2010
­31
­Figure
10. Timeline for Trailwoods LID Demonstration Project.
MONITORING PLAN (element i)
Every Watershed Based Plan requires a monitoring plan to gauge the overall success of
restoration and remediation efforts. The goal of the monitoring plan for this WBP will be
to develop a long­range
monitoring program that will oversee the restoration of the
beneficial use support in the watershed and preserve its natural resources for future
generations.
The monitoring plan for this WBP provides for development of individual monitoring
plans and associated quality assurance plans and Standard Operating Procedures for
each underlying project or effort working toward the ultimate goal of restoration of
beneficial use support. These monitoring efforts are based on Oklahoma’s Water
Quality Standards and Use Support Assessment Protocols which define the process by
which beneficial use support can be determined. Technical assistance in developing
these plans can come from various sources, including the Oklahoma State Agency peer
review process.
Methodologies developed for use in this WBP will be selected to provide: 1) a
quantifiable measure of changes in parameters of concern, 2) success measures that
can be easily understood by cooperators and stakeholders with a variety of technical
backgrounds, and 3) consistent, compatible information throughout the watershed.
Monitoring will focus on the primary causes of impairment, as listed in the 303(d) list,
but will also consider related causes that may exacerbate the impacts of the primary
causes or may ultimately reach impairment levels without improved management. As
the WBP evolves and expands to be more inclusive of all the parameters of concern, it
is anticipated that this list will expand and contract. At this time, the following
parameters will continue to be monitored in the Lake Thunderbird watershed:
· Water quality: nutrients, sediments, suspended solids, fecal bacteria, dissolved
oxygen, temperature, pH, conductivity, alkalinity, hardness, turbidity, chlorophyll­a,
BOD5
Lake Thunderbird WBP June 2010
­32
­
· Parameters for watershed model (TMDL) development: total organic carbon (TOC)
and dissolved organic carbon (DOC)
· Hydrologic budget: in­stream
flows, infiltration rates, aquifer recovery, groundwater
levels
· Landuse/land cover: acreage in different landuses, quality and type of land cover,
timing and other variables of associated management practices
· Riparian condition: extent and quality of riparian zones in the watershed to include
quality and type of vegetation, degree of impact or stability, condition of
streambanks, and primary source of threat or impact
· Aquatic biological communities: assessment of the condition of fish and benthic
macroinvertebrate communities related to reference streams and biocriteria
· BMP and other implementation efforts: type, extent, and specific location of
practices to include an estimate of the potential load reduction due to
implementation
· Behavioral change: participation in Watershed Based Plan­related
activities and
behavioral changes of affected communities
With each WBP­related
program, as well as for the WBP as a whole, baseline
conditions will be established and monitored prior to implementation. A monitoring
schedule and Quality Assurance Project Plan (QAPP) will be developed based on the
type of project and timing of its implementation. Monitoring results will be reported to
the appropriate entities as defined in the QAPPs.
Baseline Data
Water Quality
The baseline data to evaluate progress in the Lake Thunderbird Watershed has been
established by several monitoring efforts in the watershed. Until a TMDL is drafted and
officially approved, water quality in this WBP will be guided by the following:
· Oklahoma Integrated Report – Clean Water Act Section 303(d) List of Waters
needing a TMDL, 2008. Lake Thunderbird, Hog Creek, West Hog Creek, Elm
Creek, East Elm Creek, and Moore Creek are of concern because they are on
the 2008 303(d) list as impaired due to one or more of the following: chlorophyll­a,
turbidity, pathogens, low dissolved oxygen, or TDS.
· OCC monitoring – Elm Creek was monitored monthly as part of the “East of I­35
Project” from 2/1999 – 3/2001. In addition, West Elm Creek has been monitored
as part of the Blue Thumb project from 5/1998 – 6/2006.
· OWRB BUMP monitoring – Lake Thunderbird has been monitored quarterly for
one year every other year since 1998. This data was the basis for the SWAT
modeling performed by Vieux (2007).
· City of Oklahoma City Stormwater Division monitoring – Data was collected
for Hog Creek, West Hog Creek, and East Elm Creek as part of a watershed
characterization project in 2004 and 2005.
Lake Thunderbird WBP June 2010
­33
­Hydrologic
Budget
· USGS – There is one USGS stream gauge near the watershed, just below Lake
Thunderbird on the Little River.
Landuse/Land Cover
· NRCS and OCC – Color digital orthophotos (2003).
· OCC and contractors – Modeling the Lake Thunderbird Watershed Using
SWAT 2000 using geospatial data provided by the Association of Central
Oklahoma Governments (ACOG) Water Services Division, current as of 2000
(Vieux 2007). ACOG assembled and analyzed future landuse plans projected to
the year 2030 based on information provided by the municipalities within the
watershed.
Riparian Condition
· NRCS and OCC – Color digital orthophotos (2003).
· OCC and contractors – Modeling the Lake Thunderbird Watershed Using
SWAT 2000 (Vieux 2007).
Best Management Practices and Other Implementation Efforts (Coverages)
· NRCS/FSA – Records of specific practices installed and associated
costs of programs such as EQIP
· OCC and contractors – Estimates of load reductions related to installation of
specific practices through computer modeling
· ODEQ – Permit upgrades for NPDES permitees in the watershed
· OWRB – Infrastructure upgrades supported through the State Revolving Fund
Loan program
Data Collection Responsibilities
Responsibility for the collection of additional data of the types described above will
reside with project managers of the individual projects as detailed in individual work
plans. These project managers will be responsible for ensuring that the data is
submitted to the ODEQ for inclusion in the Oklahoma State Water Quality Database,
which will ultimately be uploaded to the National STORET database. Data reporting
under individual workplans will also be the responsibility of the project managers.
Monitoring results for all projects will be available and accessible to the public through
the posting of final reports on agency websites.
In addition to those monitors to be identified in the workplans of the individual projects
under this WBP, the following groups will be involved in monitoring activities:
· Oklahoma Water Resources Board (OWRB): Beneficial Use Monitoring Program
and Oklahoma Water Watch Monitoring Program
· Oklahoma Conservation Commission (OCC): Priority Watershed Project
Monitoring, Rotating Basin Monitoring, and Blue Thumb Project Monitoring; data
Lake Thunderbird WBP June 2010
­34
­collected
will be in support of both the 319 implementation project and the
ODEQ’s TMDL/WBP development for Lake Thunderbird
· U.S. Geological Survey (USGS): surface and groundwater quality and quantity
monitoring and special studies
Monitoring Details
Stream Monitoring
The OCC installed five autosamplers in the Thunderbird Watershed at the locations
given in Table 9 and Figure 11. These autosamplers collected continuous, flow­weighted
composited samples from April 2008 through April 2009. Grab samples were
collected at these locations as well, as detailed in Table 10. This data is being used by
the ODEQ to develop the TMDL for the lake and to establish pre­implementation
loads
in the major tributaries to the lake.
Table 9. Autosampler locations in the Lake Thunderbird Watershed.
Site Name WBID Legal Latitude Longitude
Little River @ 17th OK520810­00­0080W
NW¼ SE¼ SE¼
Section 22­10N­3W
35.3235 ­97.4963
West Elm Creek @ 134th OK520810­00­0140P
SE¼ SW¼ SW¼
Section 14­10N­2W
35.334 ­97.3854
Little River @ 60th OK520810­00­0080H
SE¼ SE¼ SE¼
Section 1­9N­2W
35.2778 ­97.3536
Rock Creek @ 72nd OK520810­00­0090C
NW¼ NW¼ NW¼
Section 17­9N­1W
35.261 ­97.3354
Hog Creek @ 119th OK520810­00­0030G
SE¼ SE¼ SW¼
Section 12­10N­1W
35.3483 ­97.2585
Table 10. OCC analytical parameters and sampling frequency.
Parameter Collection Frequency
Dissolved Oxygen, Conductivity, pH, Temperature, Alkalinity,
Turbidity, Instantaneous Discharge
weekly (in­situ)
;
high flow events
Total Organic Carbon, Ortho­phosphorus
(dissolved),
Nitrate/Nitrite (dissolved), Ammonia (dissolved), TSS
weekly grab samples;
high flow events
Total Phosphorus, TKN
weekly autosampler samples;
high flow events;
grab samples when
autosampler failure events
Dissolved Organic Carbon grab samples every 3 weeks
Chloride, Sulfate, Hardness, TDS monthly grab samples;
high flow events
E. coli, Enterococcus
weekly grab samples
from April 1 – October 30;
high flow events
Precipitation, Accumulated Flow weekly download;
high flow event download
Lake Thunderbird WBP June 2010
­35
­#
#
#
#
#
Cleveland Co.
Oklahoma Co.
Little River
West Elm Creek
Hog Creek
Rock Creek
Lake Thunderbird
Lake StanleyD raper
Lake Thunderbird Watershed
# Autosamplers
OSAG E
TE XAS
KA Y
ELL IS
BE AVE R
CADD O
CMI AR RO N
LE FL O RE
WO OD S
MCC URT AI N
GR AD Y
KOI WA
ATOK A
GRAN T
CR EEK
BRY AN
MA J OR
DE WEY BLANI E
HAR PE R
CUS TE R
PTI T S BUR G
CR AI G
IL NC OLN
NO BLE
WA S HIT A
LO GA N
GARV NI
GARF I ELD
TIL LM AN
PAY NE
PUSH M AT AH A
ALFA LFA
CA RTE R
LO VE
MAY ES
WO ODWAR D
COAL
HUGH ES
ADAIR
COM ANC H E
BE CKH AM
TUL SA
GREE R
CAN AD IA N
JA CKS O N
LA TIM ER
ROG ER MIL LS
STEP HE NS
RO G ER S
CH OC TAW
COT T O N
KNI G F IS HER
MU SK OGE E
DE LAWARE
HAS KE L
CH ER OKEE
PA WNEE
MC I NTO S H
JE FF ERS O N
NOWAT A
MCC L ANI
PON TO T OC
OKLA H OM A
SE QU OYAH
SE MI NO LE
OK M ULGEE
HAR M ON
JO HNS TON
OK FUS KEE
OT T AWA
WA G ON ER
MU R RA Y
POTTA WAT O MI E
CLEV ELAN D
MARS HAL L
WAS HNI GTO N
S
N
W E
Figure 11. Location of autosamplers in the Lake Thunderbird watershed.
OCC will rely on OWRB lake monitoring data to assess whether or not practices have
resulted in improved lake water quality throughout the project. Biological and habitat
monitoring will not be completed as part of this project in order to minimize project
expenses and since the project size is unlikely to significantly impact habitat availability
in the watershed. In addition, specific single landuse areas will be sampled during
runoff events for better model calibration.
In the Trailwoods project, storm water quality and quantity differences between the two
streets (conventional versus LID) will be assessed using continuous flow monitoring
systems (e.g., weirs or flumes with data­logging
pressure transducers or bubblers),
automatic flow­activated
composite samplers, and tipping­bucket
rain gauges at the
base of each street. Composite storm water samples will be analyzed for physical
parameters (e.g., pH, dissolved oxygen, temperature, specific conductance, etc.), total
suspended solids, biochemical oxygen demand, total and dissolved reactive
phosphorus, nitrate­nitrogen,
ammonia­nitrogen,
copper, lead, zinc, oil and grease, and
selected common herbicides and pesticides. Suspended sediment concentration may
be substituted for TSS if it is cost comparable. Storm hydrographs will be developed
and evaluation will include calculation of runoff volumes, peak discharge, runoff depths,
lag times, concentration changes, and area­adjusted
mass loadings and exports. It is
hypothesized that significant differences will be realized between the two watersheds.
Monitoring for this project will not begin until construction is complete, tentatively
January 2011. Additional water quality monitoring will be necessary to document
success of other LID implementation areas as they are implemented. This monitoring
Lake Thunderbird WBP June 2010
­36
­will
be funded under future project grants, and details will be provided in updates to the
WBP.
Lake Monitoring
The OWRB will continue to monitor Lake Thunderbird as part of the BUMP. This
involves quarterly sampling every other year in which the following parameters are
monitored: temperature, pH, dissolved oxygen, salinity, dissolved oxygen % saturation,
oxidation­reduction
potential (redox), specific conductance, total dissolved solids (TDS),
turbidity, Secchi disk depths, nitrate nitrogen, nitrite nitrogen, ammonia nitrogen,
kjeldahl nitrogen, orthophosphorus, total phosphorus, true color, chloride, sulfate, total
alkalinity, chlorophyll­a,
and pheophytin. Vertical water quality profiles are recorded at
one meter intervals from the lake surface to the lake bottom for at least three sites per
reservoir: in the central pool area near the dam (lacustrine zone), in the upper portion
of the lake and in the major arms of the water body (riverine zone), and in the area
between the lacustrine zone and the riverine zone (transitional zone). In addition, the
OWRB is contracted to monitor the lake annually from April through October to provide
information to the COMCD.
Landuse/Landcover
Comparisons of landuse/landcover will be made throughout the project as new data
becomes available. The SWAT model used geospatial landuse data provided by the
Association of Central Oklahoma Governments (ACOG) Water Services Division,
current as of 2000, and this data will be requested periodically as new coverages
become available. In addition, census data will be updated in the WBP as it is released
so that the expected urbanization in the watershed is accurately represented.
Best Management Practice Implementation
Summaries of BMP implementation will be included in final reports at the conclusion of
each project in the watershed. Maps showing implementation in relation to hotspot
areas (based on SWAT modeling) in the watershed will be included in the assessment
of BMP implementation. This information will be inserted into the WBP as it becomes
available.
Benefits of the Monitoring Plan
Implementation of this monitoring plan will enable Lake Thunderbird watershed partners
to meet the goals of the WBP, which is ultimately to restore beneficial use support to
waters of the watershed. Implementation of the monitoring plan will help further define
areas of the watershed where restoration activities should be focused to realize the
optimum benefit for the investment as well as evaluate the impacts (realized and
potential) of implementation efforts. Collection of the data described under this
monitoring plan will help define the relative contributions from various sources in the
watershed and the processes contributing to water quality degradation in the watershed.
Finally, continued collection of this data and evolution of the monitoring plan for the
watershed will allow the program to adapt to meet the changing needs of watershed
protection in the Lake Thunderbird Watershed.
Lake Thunderbird WBP June 2010
­37
­TECHNICAL
and FINANCIAL ASSISTANCE NEEDED (element d)
Funding needs are difficult to anticipate and will likely change over time. The estimated
costs associated with the current projects in the watershed are highly conservative and
will change as the TMDL is finalized and further information becomes available.
Potential project funding in this watershed includes money from the EPA 319 program,
state programs (OCC, OWRB, ODEQ), municipalities (Norman, Moore, Oklahoma City),
and private entities (COMCD). Additional funds beyond those available in the OCC
2007­2008
319 grants will be necessary to complete the proposed implementation, so
the project will be executed in a phased approach. Initial estimates of the funds to carry
out phase 1 of the Trailwoods LID project are shown in Table 11, below, along with
activities of other agencies in the watershed.
Technical assistance will be in the form of peer review of proposed projects from the
NPS working group and data­sharing
from the entities listed in Table 11. OCC is
working with the cities in the watershed to educate, monitor, model, and implement
BMPs. Although EPA funds have been and will likely continue to be allocated toward
this effort, cities are devoting considerable funds towards activities in the watershed as
well. OCC will work with cities to provide a better accounting of their anticipated needs
for funding, as well as their ongoing investments in water programs which may be used
for in­kind
match of federal funds, in future iterations of the WBP.
Table 11. Funding for specific projects/efforts.
Task Program Federal State Total Agency Status
Trailwoods 319 LID
Demo Project (phase 1) $297,578 $214,656 $512,234 OCC Ongoing
Lake Thunderbird
Aeration Project $692,773 OWRB Ongoing
Erosion Control /
Shoreline Stabilization
Demo Project
$6,500 OWRB Completed
BMP
Implementation
Stormwater Master
Plan Projects $83,000,000 City of
Norman Planned
319 Project /
Blue Thumb $Education and 182,724 OCC Planned
Outreach Stormwater Master
Plan Projects ? City of
Norman Planned
Autosampler monitoring
in support of TMDL $10,249 OCC /
ODEQ Completed
Trailwoods 319 LID
Demo Project $44,940 OCC Planned
Monitoring
BUMP & COMCD
(Lake Thunderbird only)
$90,000
annually
OWRB /
COMCD Ongoing
Computer
Modeling
SWAT project to target
NPS pollution $89,774 $89,774 OCC Completed
Lake Thunderbird WBP June 2010
­38
­HSPF
watershed model
for TMDL $78,000 ODEQ Ongoing
EFDC lake model for
TMDL $164,774 ODEQ Ongoing
REFERENCES
Cole, Carol. 2007. Council to consider storm water plan contract. Norman Transcript,
July 9, 2007.
COMCD. 2006. Rock Creek Watershed Analysis and Water Quality Evaluation.
Prepared for the Central Oklahoma Master Conservancy District by Vieux and
Associates, Inc.
ODEQ. 2008. Integrated Report. Oklahoma Department of Environmental Quality.
McNab, W.H. and P.E. Avers. 1994. Ecological Subregions of the United States. USDA,
Forest Service.
OWRB. 2001a. Shoreline Erosion Control Plan, Lake Thunderbird, Cleveland County,
Oklahoma. AllEnVironment Consulting, for Oklahoma Water Resources Board.
OWRB. 2001b. Evaluation of Lake Thunderbird Water Quality Management Practices
for the Central Oklahoma Master Conservancy District. Oklahoma Water
Resources Board.
OWRB. 2002. Lake Thunderbird Capacity and Water Quality 2001, Final Report for the
Central Oklahoma Master Conservancy District. Oklahoma Water Resources
Board.
OWRB. 2003. Lake Thunderbird Algae and Water Quality, Final Report for the Central
Oklahoma Master Conservancy District. Oklahoma Water Resources Board.
OWRB. 2008. Oklahoma Water Quality Standards, Oklahoma Administrative Code,
Chapter 45. Oklahoma Water Resources Board.
OWRB. 2008. Implementation of Oklahoma’s Water Quality Standards, Oklahoma
Administrative Code, Chapter 46. Oklahoma Water Resources Board.
OWRB. 2006. Agency Rule Report, Amendments to Title 785. Oklahoma Water
Quality Standards, Oklahoma Administrative Code, Chapter 45. Oklahoma
Water Resources Board.
Vieux and Associates, Inc. 2007. Lake Thunderbird Watershed Analysis and Water
Quality Evaluation. Report for Oklahoma Conservation Commission.